Use for the prevention or treatment of chronic pain

Abstract

The present disclosure provides a use for preventing or treating chronic pain in a subject in need thereof, comprising administering to the subject an effective amount of Lactococcus lactis DSM 27109 composition.

Description

Technical Field

[0001] This disclosure relates to a lactic acid bacterium, and more particularly to a lactic acid bacterium strain for the prevention or treatment of chronic pain in subjects in need. Background Technology

[0002] Chronic pain impacts a wider range of people than previously thought. Its prevalence can be as high as 40%, and its various clinical manifestations, such as back pain, musculoskeletal disorders, and neck pain, are leading causes of lost years of disability. The personal, social, and economic burdens associated with chronic pain are immense.

[0003] Because of its multifaceted nature, chronic pain has always been difficult to define fully. Recently, the International Association for the Study of Pain (IASP) expanded its definition of chronic pain to "an unpleasant sensory and emotional experience that is associated with, or similar to, actual or potential tissue damage." Therefore, chronic pain is now recognized as pain that can occur even in the absence of clear tissue damage. Furthermore, pain is inherently subjective, and patients' accounts of their pain should be accepted in the absence of contrary evidence; however, clinicians may consider other methods (such as facial expression and imaging) to assess pain and identify its causes.

[0004] Although in practice, different types of pain mechanisms often overlap considerably within the same patient or between different patients, and pain classification is generally considered a continuous process, the currently widely accepted classification of chronic pain includes three types: nociceptive pain (caused by tissue damage), neuropathic pain (caused by nerve damage), and nociplastic pain (caused by a sensitized nervous system). Nociplastic pain is the most recently recognized classification of chronic pain. Previously, chronic pain was thought to originate from two sources: nociceptive pain, which is associated with continuous input from actual or potential tissue damage; and neuropathic pain, which is caused by damage or disease affecting the peripheral nervous system or the central nervous system (CNS). However, many chronic pain states with distinct phenotypic characteristics still exist without clear clinical evidence of nociceptive or neuropathic involvement. In 2016, the term "nociplastic pain" was proposed as a mechanistic descriptor to define a chronic pain state characterized by abnormal nociceptive function without obvious nociceptor activation or neuropathy.

[0005] Nociplastic pain represents a dynamic process involving the interaction of multiple mechanisms that can trigger or amplify pain. This pain can be primary or triggered by one or more pain-generating factors, which may be driven by the peripheral or central nervous system, psychological factors, or a combination of factors. This type of pain can be applied to a variety of clinical conditions, sharing similar neurophysiological mechanisms and potentially involving different organ systems. However, the underlying pathogenesis of nociplastic pain remains incompletely understood. Therefore, the treatment and care of these patients is challenging, with treatment strategies primarily focusing on symptom relief rather than complete eradication, and may be combined with other therapies, including improving physiological function and quality of life indicators.

[0006] Existing reports indicate that most medications provide only moderate efficacy and are often accompanied by adverse reactions, which are more likely to occur in nociplastic pain (Jason LA et al., Psychosom. Med. 2000;62: 655-63). Furthermore, although strategies such as acceptance and commitment therapy, emotional expression, and psychodynamic therapy are generally recommended for the treatment of chronic pain, the evidence for their effectiveness (and adverse reactions) is insufficient (Williams ACC et al., Cochrane Database Syst. Rev. 2020; 8: CD007407), a situation consistent with the treatment of many chronic pain conditions. Nevertheless, nociplastic pain is known to respond differently to treatment than nociceptive pain, exhibiting lower responsiveness to peripherally oriented therapies such as anti-inflammatory drugs, opioids, surgery, or injections.

[0007] Therefore, there remains an urgent need for novel and alternative options that can effectively prevent or treat chronic pain (such as injury plasticity pain) while reducing the adverse side effects common to many other analgesics. Summary of the Invention

[0008] This disclosure provides a composition for the prevention or treatment of chronic pain, comprising a lactic acid bacterium and its carrier. In at least one embodiment, the lactic acid bacterium is *Lactococcus lactis* (…). Lactococcus lactis The lactic acid bacteria are deposited under DSMZ accession number DSM 27109. In at least one embodiment, the lactic acid bacteria are selected from one of the following groups: culture, concentrate, paste, liquid, dried product, diluted product, or pulverized product. In at least one embodiment, the dried product is a spray-dried powder, freeze-dried powder, vacuum-dried powder, or drum-dried powder. In at least one embodiment, the lactic acid bacteria are in a live form or a heat-inactivated bacterial form. In at least one embodiment, the composition of this disclosure is a dietary composition or a pharmaceutical composition.

[0009] In at least one embodiment, the lactic acid bacteria are administered orally to the subject. In at least one embodiment, the effective amount is at least 1 × 10⁻⁶. 6 CFU, at least 1×10 7 CFU, at least 1×10 8 CFU, at least 1×10 9 CFU, at least 1×10 10 CFU or at least 1×10 11 CFU, which includes 5×10 6 CFU, 5×10 7 CFU, 5×10 8CFU, 2×10 9 CFU, 3×10 9 CFU, 4×10 9 CFU, 5×10 9 CFU, 6×10 9 CFU, 7×10 9 CFU, 8×10 9 CFU, 9×10 9 CFU, 2×10 10 CFU, 3×10 10 CFU, 4×10 10 CFU, 5×10 10 CFU, 6×10 10 CFU, 7×10 10 CFU, 8×10 10 CFU, 9×10 10 CFU, 2×10 11 CFU, 3×10 11 CFU, 4×10 11 CFU, 5×10 11 CFU, 6×10 11 CFU, 7×10 11 CFU, 8×10 11 CFU and 9×10 11 CFU, but not limited to this.

[0010] In at least one embodiment of this disclosure, a method for preventing or treating chronic pain in a subject with a need is also provided. In at least one embodiment, the method of this disclosure includes administering an effective amount of [unspecified substance] to the subject with a need. Lactococcus lactis DSM 27109.

[0011] In at least one embodiment, the chronic pain is nociplastic pain. In at least one embodiment, the nociplastic pain is caused by fibromyalgia, irritable bowel syndrome, bladder pain syndrome, complex focal pain syndrome type I, or temporomandibular joint disorder. In at least one embodiment, the nociplastic pain is generalized sensitization, functional visceral pain, or regional somatosensory sensitization. In at least one embodiment, the generalized sensitization is pain caused by fibromyalgia. In at least one embodiment, the functional visceral pain or the regional somatosensory sensitization is pain caused by irritable bowel syndrome.

[0012] In at least one embodiment of this disclosure, a method for reducing pain neurotransmitters is also provided for the prevention or treatment of chronic pain in a subject in need, comprising administering an effective amount to the subject in need.Lactococcus lactis DSM 27109. In at least one embodiment, the neurotransmitter is substance P.

[0013] This disclosure also provides a method for preventing or treating fibromyalgia in a subject with a need, comprising administering an effective amount of [unspecified substance] to the subject. Lactococcus lactis DSM 27109. In at least one embodiment of this disclosure, Lactococcus lactis Administration of DSM 27109 reduces nociceptive plasticity pain in the subjects with fibromyalgia. In at least one embodiment, the nociceptive plasticity pain in the fibromyalgia is generalized sensitization. In at least one embodiment of this disclosure, Lactococcus lactis DSM 27109 administration improves depression for the prevention or treatment of fibromyalgia in subjects in need.

[0014] This disclosure also provides a method for preventing or treating irritable bowel syndrome in a subject who has the need, comprising administering an effective amount of [unspecified substance] to the subject. Lactococcus lactis DSM 27109. In at least one embodiment of this disclosure, Lactococcus lactis Administration of DSM 27109 reduces nociceptive plasticity pain of irritable bowel syndrome in the subjects. In at least one embodiment, the nociceptive plasticity pain of irritable bowel syndrome is regional somatosensory sensitization. In at least one embodiment of this disclosure, Lactococcus lactis The administration of DSM 27109 reduces the amount of substance P for use in subjects who require it for the prevention or treatment of irritable bowel syndrome. In at least one embodiment of this disclosure, Lactococcus lactis Administration of DSM 27109 increases mucin production for use in the prevention or treatment of irritable bowel syndrome in subjects who require it. In at least one embodiment of this disclosure, Lactococcus lactis The administration of DSM 27109 enhances the function of the intestinal barrier for the prevention or treatment of irritable bowel syndrome in subjects in need. Attached Figure Description

[0015] A deeper understanding of this disclosure can be obtained by reading the following description of the embodiments and referring to one or more of the accompanying drawings.

[0016] Figure 1 This is a line graph showing the change in the paw withdrawal (PW) threshold over time in response to mechanical stimulation in an animal model of fibromyalgia. * indicates comparison with the baseline (BL). p <0.05, ** indicates a comparison with the baseline value. p < 0.01.

[0017] Figure 2 This shows the relative resting time during the forced swim test (FST) in an animal model of fibromyalgia. # indicates comparison with the muscle pain (MP) group. p < 0.05.

[0018] Figure 3 The visceral response before (baseline) and after 5-HTP injection is shown in the normal saline group and the DSM 27109 group, respectively. ** indicates comparison with baseline. p < 0.01, *** indicates a value compared to the baseline. p < 0.001.

[0019] Figure 4 This displays the immunoreactivity of substance P in the L6 and S1 spinal cord. RFU represents relative fluorescence units. * indicates comparison with the control group. p < 0.05, ## indicates comparison with the physiological saline group p < 0.01.

[0020] Figure 5 This shows the quantitative results of the Alcian blue positive region in a remote colon section of a rat. *** indicates the difference compared to the control group. p < 0.001, ### indicates comparison with the physiological saline group p < 0.001.

[0021] Figure 6 The total fluorescent region of occludin and ZO-1 in the distal colon of rats is shown. * indicates comparison with the control group. p < 0.05, ### indicates comparison with the physiological saline group p < 0.001.

[0022] Figure 7 This figure shows the foot retraction threshold at different time points in a somatosensory hypersensitive animal model treated with different strains of lactic acid bacteria in response to mechanical stimulation. Error bars represent mean ± standard deviation. * indicates comparison with the saline group. p < 0.05, *** indicates a difference compared to the saline group. p < 0.001. Detailed Implementation

[0023] The following examples are used to illustrate this disclosure, and those skilled in the art can easily conceive of other uses of this disclosure based on the disclosure in this specification. It is obvious that one or more embodiments of this disclosure can be implemented without detailed description of specific aspects. This disclosure can also be implemented or applied based on the description of different examples. To implement this disclosure, the following examples can be modified or changed according to different applications without departing from the scope of this disclosure. The headings or subheadings used in this disclosure are for the convenience of the reader only and should not affect the scope of this disclosure.

[0024] In this disclosure, all illustrative or technical terms are to be interpreted in a way that is readily understood by one of skill in the art. However, the meaning of a term may vary depending on the intent of one of skill in the art, relevant case law, or the emergence of new technologies. Furthermore, some terms may be arbitrarily selected by the applicant; in such cases, the meaning of the selected term will be detailed in the description of this disclosure. Therefore, the terms used in this disclosure are defined based on their inherent meaning and in conjunction with the entire contents of this specification.

[0025] The singular forms “a (a) / (an)” and “the” used in this disclosure, unless expressly and unambiguously limited to a single object, include the meaning of plural. Furthermore, unless the context clearly indicates otherwise, the term “or” may be used interchangeably with the terms “and / or”.

[0026] Furthermore, when a part "includes" or "comprises" a component or a step, unless otherwise specifically stated to the contrary, the part may further include other components or other steps without excluding the presence of such other components or steps.

[0027] As used herein, the term "at least one," when describing a list of one or more elements, is understood to mean selecting at least one element from any one or more items in the list, but does not necessarily include every item listed, nor exclude any combination of elements in the list. This definition also allows for the optional presence of elements outside the list referred to by the term "at least one," regardless of whether those elements are related to the listed elements. Therefore, as a non-limiting example, "at least one A and B" (or equivalently, "at least one A or B," or equivalently, "at least one A and / or B") may, in one embodiment, refer to at least one A, or may include more than one A, and exclude B (and may optionally include other elements besides B); in another embodiment, it may refer to at least one B, or may include more than one B, and exclude A (and may optionally include other elements besides A); in yet another embodiment, it may refer to at least one A, or may include more than one A, and at least one B, or may include more than one B (and may optionally include other elements).

[0028] The term "an effective amount" refers to the amount of active ingredient required to achieve the effect of reducing, inhibiting, or preventing chronic pain in a subject. The required effective amount will vary, as will be understood by those skilled in the art, and such variations may depend on the route of administration, the use of excipients, and the possibility of concurrent use with other therapeutic treatments.

[0029] The terms “subject” and “individual” as used herein are used interchangeably and refer to animals such as mammals, including the human species. The term “subject” is intended to include both males and females unless a particular sex is specifically specified. Examples of non-human animal subjects that are not restrictive include: rodents such as mice, rats, hamsters, and guinea pigs; rabbits; dogs; cats; sheep; goats; cattle; horses; and non-human primates such as apes and monkeys.

[0030] As used herein, the terms “prophylactic,” “preventing,” or “prevention” refer to preventive or avoidance measures taken against a disease or its symptoms or condition. These measures include, but are not limited to, administering or applying one or more active substances to a subject who has not yet been diagnosed with the disease or its symptoms or condition, and who may be susceptible to or prone to the disease (e.g., chronic pain). The purpose of such preventive measures is to avoid, prevent, or postpone the occurrence of the disease or its symptoms or condition.

[0031] As used in this specification, the terms “treat,” “treating,” or “treatment” mean the administration or application of one or more active substances to a subject suffering from an illness, symptoms or condition of the illness, or the course of the illness, with the aim of curing, restoring, alleviating, reducing, altering, correcting, improving, enhancing, or influencing the illness, symptoms or condition of the illness, disability caused by the illness, or the course of the illness.

[0032] As used in this specification, the term "administration" means placing a formulation of an effective dose of lactic acid bacteria as described herein into a subject by a method or route that allows the formulation to be at least partially located at a desired site. The formulation described herein can be administered via any suitable route to produce an effective therapeutic effect on a subject, i.e., the administration delivers the formulation to a desired site in the subject, and the site is at least partially delivered with the formulation. Illustrative methods of administration include, but are not limited to, injection, infusion, drip, or oral administration.

[0033] This disclosure provides a lactic acid bacteria, a composition comprising said lactic acid bacteria, and a method of preventing or treating chronic pain by administering said composition to a subject in need. In the context of this disclosure, the term "chronic pain" means pain lasting longer than one month, such as longer than three months, but not limited thereto. According to the International Association for the Study of Pain (IASP), chronic pain means an unpleasant sensory and emotional experience associated with, or similar to, actual or potential tissue damage. This definition acknowledges that pain may occur in the absence of identifiable tissue damage, such as in fibromyalgia. Chronic pain can be categorized into three main types: nociceptive pain, neuropathic pain, and nociplastic pain. Nociceptive pain is caused by activity in neural pathways, which is secondary to actual stimuli or stimuli that may cause tissue damage. Nociceptive pain is the most common form of chronic pain, encompassing arthritis and most forms of spinal pain. According to the IASP, neuropathic pain is pain caused by damage or disease affecting the somatosensory nervous system. Compared to nociceptive pain, neuropathic pain is typically associated with sensory abnormalities such as numbness and allodynia, and is characterized by more pronounced pain paroxysmal. It may also manifest as neurological abnormalities depending on the affected nerve. Common terms used to describe nociceptive pain include "aching" and "throbbing," while neuropathic pain is usually described with adjectives such as "lancinating" and "shooting."

[0034] Approximately 15% to 25% of chronic pain is neuropathic pain, with the most common conditions including diabetic neuropathy, postherpetic neuralgia, and radiculopathy. Unlike most forms of nociceptive pain and acute nerve injury, chronic neuropathic pain is consistently maladaptive. Nociplastic pain refers to pain caused by abnormal pain signal processing, without clear evidence of tissue damage or a definite pathology of the somatosensory nervous system. This type of pain is also known as functional pain syndrome, and its conditions include pain states such as fibromyalgia, irritable bowel syndrome, and possibly nonspecific back pain. The pathophysiological mechanisms causing this condition mainly involve enhanced sensory processing and weakened inhibitory pathways. Nociplastic pain includes: pervasive sensitization in fibromyalgia; functional visceral pain or visceral hypersensitivity in irritable bowel syndrome or bladder pain syndrome; regional somatosensory sensitization in complex focal pain syndrome type I or temporomandibular joint disorders; peripheral sensitization due to sodium ion channel proliferation or sympatho-afferent coupling; central sensitization due to N-methyl-D-aspartate (NMDA) receptor activation or cortical remodeling; decreased function of descending inhibitory systems such as the periaqueductal gray and rostroventromedial medulla; and activation of the immune system, including glial cells, chemokines, cytokines, and other inflammatory mediators. Common injury plasticity pain syndromes include chronic generalized pain, fibromyalgia, chronic lower back pain of unknown cause, chronic temporomandibular joint pain disorder, irritable bowel syndrome, chronic primary bladder pain syndrome, and chronic primary pelvic pain syndrome.

[0035] Example The exemplary embodiments of this disclosure will be further illustrated in the following examples, but should not be construed as limiting the scope of this disclosure.

[0036] Materials and methods Lactococcus lactis Preparation of DSM 27109 Separated Lactococcus lactisDSM 27109 (hereinafter referred to as DSM 27109) was inoculated into de ManRogosa Sharpe (MRS) medium (Criterion, Hardy Diagnostics, Santa Maria, CA, USA) and anaerobically cultured at 37°C for 18 hours. The bacterial cells were then collected by centrifugation at 6,000 × g for 10 minutes. The bacterial pellet was resuspended in MRS medium containing 12.5% ​​glycerol and adjusted to a final concentration of 5 × 10⁻⁶ mg / mL. 10 Colony-forming units (CFUs) are aliquoted and stored at -20°C until use. Before oral administration to rodents, aliquoted samples are preheated at 37°C for 1 hour, centrifuged at 6,000 × g for 10 minutes, the supernatant is removed, and the samples are resuspended in phosphate-buffered saline (PBS).

[0037] animal Male C57BL / 6J mice (8 weeks old) were purchased from the laboratory animal center. Adult male Sprague-Dawley (SD) rats (300–400 g) were obtained from relevant institutions. All animals were housed in a temperature-controlled environment (22 ± 2 °C) with a 12-hour light-dark cycle, and had free access to standard laboratory mouse feed and tap water. All experimental procedures were approved by the relevant institutions.

[0038] A mouse model of acid-induced muscle pain This experiment used the acid-induced muscle pain (MP) model reported by Lin YL et al. (Elife. 2022 Nov. 15; 11:e78610) as a preclinical fibromyalgia-like MP model. In short, after anesthesia, all mice in the MP group and control group were injected with 20 μL of acidic saline (pH 4.0) or neutral saline (pH 7.2) into the left gastrocnemius muscle on day 0. Three days later (day 3), acidic or neutral saline was injected again into the same gastrocnemius muscle.

[0039] von Frey filament test Mechanosensitive hypersensitivity was assessed using the von Frey filament tenderness test. A series of von Frey filament tenderness test needles with increasing rigidity (0.04 to 1.4 g) were applied to the plantar surface of both hind feet. Each needle was used to stimulate the plantar surface five times, and the lowest stimulus force (g) that elicited at least three withdrawal responses was recorded as the mechanosensitive threshold.

[0040] Forced swim test The forced swimming test (FST) was conducted using a transparent acrylic cylindrical container (25 cm high, 10 cm in diameter) filled with water to a depth of 16 cm. Mice were placed in water maintained at a temperature of 20°C to 22°C for 6 minutes. The time spent at rest was measured using the video tracking software EthoVision XT 13 (Noldus Information Technology, Leesburg, Virginia, USA). This metric served as an assessment of depressive behavioral performance.

[0041] Electromyography recording of colorectal distension induced by 5-HTP injection-induced visceral hypersensitivity. Colorectal distension (CRD) combined with electromyography (EMG) recording was performed to assess the degree of visceral hypersensitivity (VH), following a previous study (Lu CL et al., Gastroenterology 137:1040-1050). First, under anesthesia, a Teflon-coated stainless steel EMG electrode (7 strands, AM Systems, Inc., Carlsberg, Washington, USA) was implanted into the external oblique muscle of rats. The electrode lead was then led out through the nape of the neck. Following electrode implantation, rats were given a two-week acclimatization period. To allow rats to acclimatize to the experimental environment, they were individually placed in a circular, transparent plastic tube (6 cm in diameter, 25 cm in length) for 30 minutes daily before the CRD experiment.

[0042] The expansion balloon used in CRD was made from a 7 cm long latex glove finger and fixed to a rectal catheter (Medtronic, Skovlunde, Denmark). To balance the tension of the balloon walls, it was inflated and left to stand overnight. During the CRD test, the inflatable device was inserted into the rectum of awake rats through the anal tube and fixed at the base of the tail. This device was connected to a barostat machine (Medtronic, Denmark), and the colon was expanded to a set pressure (30, 60, or 80 mmHg) by inflating the balloon. Each expansion lasted 10 seconds, with a 30-second interval between expansions. Each experimental condition was repeated four times, with a 5-minute interval between each series. To assess the visceral motor response induced by CRD, EMG data were recorded using a CED 1401 instrument and analyzed using Spike 2 software (Cambridge Electronic Design, Cambridge, UK). The raw signal is rectified offline, and the area under the curve (AUC) of the corresponding CRD response after rectification is subtracted from the AUC of the baseline activity curve for each stage to calculate the difference in AUC. At each test stage, the EMG values ​​obtained from individual expansions are averaged.

[0043] After undergoing a CRD test at baseline, rats were allowed to rest for 30 minutes. Subsequently, rats in the saline and DSM27109 groups were subcutaneously injected with 5-hydroxytryptophan (5-HTP, 5 mg per kg per rat) to induce increased visceral hypersensitivity, while rats in the control group received a subcutaneous injection of saline (200 μL per rat). All rats rested for another 30 minutes before undergoing a second CRD test to assess the degree of visceral hypersensitivity.

[0044] Injecting rats with CRD and 5-HTP can serve as an animal model of irritable bowel syndrome (IBS).

[0045] Immunofluorescence analysis of protein expression Rats were deeply anesthetized and perfused with 10% formalin fixative (JT Baker, Center Valley, Pennsylvania, USA). The L6-S1 spinal cord and distal colon were harvested and postfixed in 10% formalin at 4°C for 4 hours, followed by dehydration with 30% sucrose solution. Subsequently, the tissues were embedded in OCT gel and cut into 30 µm thick sections using a cryostat (CM1900, Leica, Germany).

[0046] L6-S1 spinal cord sections were washed with Tris-buffered saline containing 0.3% Triton X-100 (TBST), blocked with 5% skim milk powder for 2 hours, and then reacted overnight at 4°C with a primary antibody (rat anti-substance P antibody, 1:200, GTX72999, GeneTex). Subsequently, the sections were washed with TBST and reacted with a secondary antibody (rabbit anti-rat FITC 647 antibody, 1:400, Jackson ImmunoResearch) for 2 hours under light-protected conditions. Finally, the sections were washed again with TBST, mounted with Fluoromount-G mounting medium (Invitrogen), and stored at 4°C. Fluorescence signals were detected using a confocal laser scanning microscope (FV10i, Olympus, Tokyo, Japan), and image analysis was performed using MetaMorph software.

[0047] Remote colon sections were washed with phosphate-buffered saline (PBST) containing 0.25% Triton X-100, blocked for 1 hour at room temperature with 1% bovine serum albumin and 5% normal goat serum, and then reacted overnight at 4°C with primary antibodies (rabbit anti-ZO-1 antibody, 1:50, Invitrogen; rabbit anti-tight junction protein antibody, 1:25, Proteintech). Subsequently, the sections were washed with PBST and reacted for 2 hours at 2°C in the dark with secondary antibodies (goat anti-rabbit FITC antibody, 1:400, Millipore). Finally, the sections were stained with Hoechst 33258 (1:2000) for 20 minutes, washed with PBS, mounted with Fluoromount-G mounting medium, and stored at 4°C. Fluorescence signals were detected using a confocal laser scanning microscope (LSM700, Zeiss, Germany), and images were analyzed using MetaMorph software.

[0048] Histological analysis Paraffin-embedded remote colon tissue blocks were cut into 5 μm thick sections. After dewaxing and rehydration, the tissue sections were stained with Alsin blue (pH 2.5), mounted on glass slides, and observed under a microscope.

[0049] Data analysis and statistics Data were analyzed using GraphPad Prism 6 (GraphPad Software, Inc., San Diego, California, USA). Statistical significance was determined by one-way analysis of variance (ANOVA) combined with Tukey's post-hoc test or Mann-Whitney test. The significance level (p-value) is shown in the figure. Data are expressed as mean ± standard error (SEM).

[0050] Example 1. Lactococcus lactis DSM 27109 alleviates chronic pain and depression in animal models of fibromyalgia. Acid-induced muscle pain (MP) is considered a preclinical animal model of fibromyalgia in rats and mice (Sluka KA et al., Communicative & Integrative Biology 4:394-39). In this embodiment, muscle pain was induced in mice according to a standard acid-induced procedure described in the literature. In the group of mice with muscle pain, acidic saline (pH 4.0) was injected unilaterally into the gastrocnemius muscle on day 0 (baseline, BL) and day 3, respectively. After the first injection of acidic saline, the mice with muscle pain exhibited a transient decrease in the paw withdrawal (PW) threshold in both the ipsilateral ("ipsi") and contralateral ("contral") hind limbs upon stimulation with a von Frey filament tenderness test needle, such as... Figure 1 As shown, most of the acute pain responses resolved by day 3. However, the second injection triggered a persistent decrease in the foot retraction threshold that lasted for at least 10 days. In contrast, control mice (Ctrl) receiving injections of neutral saline (pH 7.2) did not show significant changes in the foot retraction threshold under von Frey filament tenderness test needle stimulation compared to the muscle pain mice.

[0051] Compared to mice with muscle pain, mice in the DSM 27109 group received oral administration of DSM27109 (1 × 10⁻⁶ per mouse per day) for 7 consecutive days prior to baseline. 9 CFU, after injection of acidic saline, showed an increase in the foot retraction (PW) threshold (e.g. Figure 1 (As shown in the image). This result shows that DSM 27109 can relieve acid-induced muscle pain (MP).

[0052] In addition to mechanical tenderness, the muscle-pain mice also exhibited a variety of affective symptoms, including depression. The forced swimming test (FST), a commonly used method for assessing depressive behavior in mice, showed that the resting time of the muscle-pain mice was significantly prolonged compared to the control group (e.g., Figure 2 As shown in the figure), their melancholic-like behaviors increased. However, the resting time was reduced in the muscle pain mice treated with DSM 27109 (as shown in the figure). Figure 2 As shown in the figure, DSM 27109 can alleviate depressive-like behaviors in a mouse model of muscle pain.

[0053] Example 2. Lactococcus lactis DSM 27109 reduces visceral hypersensitivity (VH). To evaluate the effect of DSM 27109 on 5-HTP-induced visceral hypersensitivity (VH) in rats, a colorectal distension (CRD) test was performed. Figure 3 As shown, the levels of visceral motor reflexes in the physiological saline group and the DSM 27109 group were comparable at the baseline (BL). Also as... Figure 3 As shown, compared to baseline, 5-HTP injection significantly increased visceral motor reflex levels under all three vasomotor pressures in the saline group. However, in the DSM 27109 group (which received oral administration of DSM 27109 for 14 consecutive days prior to CRD at a dose of 1 × 10⁻⁶ per rat per day), [the following results were observed]. 10 No significant increase was observed in CFU. These results indicate that DSM 27109 can alleviate 5-HTP-induced visceral hypersensitivity in rats.

[0054] Example 3. Lactococcus lactis DSM 27109 reduces the amount of substance P (SP). Substance P is a neurotransmitter associated with the transmission of pain signals to the spinal cord and brain. Previous studies have indicated that in mice treated with CRD, visceral pain signals are primarily transmitted to the L6-S1 segment of the spinal cord (Kyloh, M. et al., Front Neurosci. 5:16). To further confirm the effect of DSM 27109 on 5-HTP-induced visceral hypersensitivity (VH), immunofluorescence staining was performed to determine the amount of substance P in the L6-S1 spinal cord segment.

[0055] The results showed that in the L6 and S1 spinal cord segments, the immune response signal of substance P was higher in the saline group than in the control group, while the administration of DSM 27109 reduced the signal of substance P (e.g., Figure 4 As shown in the figure, DSM 27109 can reduce the amount of substance P in 5-HTP-induced visceral hypersensitivity (VH) rats.

[0056] Example 4: Lactococcus lactis DSM 27109 increases mucin production and strengthens the colonic barrier. Mucin is a major component of the colonic mucus barrier. To investigate whether DSM 27109 supplementation affects mucin expression in a rat model of 5-HTP-induced irritable bowel syndrome (IBS), Alsin blue staining was performed to analyze the amount of mucin produced in the distal colon. Figure 5The quantitative results of Alsin blue-positive areas in colonic sections were displayed. Compared to the control group, the saline group showed smaller positive areas of colonic mucin, indicating that 5-HTP injection damages the intestinal mucosal barrier. However, DSM27109 supplementation significantly restored colonic mucin expression. Figure 5 As shown, the area containing mucin in the DSM 27109 group was significantly larger than that in the control group.

[0057] Tight junction proteins, such as occludin and ZO-1, maintain the integrity of the intestinal barrier and regulate the permeability of ions, nutrients, and water. To assess intestinal permeability, immunofluorescence staining was used to analyze the performance of tight junction proteins and ZO-1 in the colonic mucosa. Figure 6 As shown, compared to the control group, the fluorescent regions of tight junction proteins and ZO-1 proteins were significantly reduced in the saline group of mice. After 14 days of DSM 27109 supplementation, the fluorescent regions of tight junction proteins and ZO-1 increased, and were significantly higher than those in the saline group. Overall, the data indicate that DSM 27109 supplementation can promote the expression and distribution of tight junction proteins, thereby maintaining an appropriate intestinal barrier.

[0058] Example 5: Lactococcus lactis DSM 27109 reduces somatosensory hypersensitivity To assess somatosensory hypersensitivity, a rat model was used, involving intracolonic injection of trinitrobenzenesulfonic acid (TNBS). Previous studies have shown that somatosensory hypersensitivity can persist for at least 16 weeks after TNBS-induced colonic inflammation. In short, 20 mg of TNBS was dissolved in 50% ethanol (total volume 0.4 mL) and injected into the colonic lumen 3-4 cm above the anus using a 5-6 cm 24-needle catheter, while control rats received an equal volume of physiological saline. Starting 14 days after TNBS administration, the rats received either physiological saline or different strains of lactic acid bacteria (DSM 27109, 836S, or 265P, 1 × 10⁻⁶ daily) 9 CFU was administered to rats until day 28, while control rats were orally administered saline. Somatosensory pain was assessed using the von Frey filament tenderness test on days 14, 21, and 28 following colonic treatment with either trinitrobenzenesulfonic acid or saline.

[0059] To identify the most effective lactic acid bacteria strains for relieving somatic pain, a trinitrobenzenesulfonic acid model was used to test various strains. For example... Figure 7As shown, rats developed a hypersensitivity response to mechanical stimulation after colonic treatment with trinitrobenzenesulfonic acid. However, treatment with the DSM 27109 lactic acid bacteria strain increased the somatosensory hypersensitivity threshold in rats on day 28 after trinitrobenzenesulfonic acid treatment, while the other two strains did not show this effect. These results suggest that DSM 27109 has the potential to increase the somatosensory hypersensitivity threshold and alleviate pain.

[0060] Although some embodiments of this disclosure have been described in detail above, those skilled in the art can make various modifications and changes to the disclosed embodiments without substantially departing from the teachings of this disclosure. Such modifications and changes are still covered by the scope of the appended claims.

Claims

1. The use of a composition in the preparation of a medicament for the prevention or treatment of chronic pain in a subject with a need, characterized in that, The composition contains an effective amount Lactococcuslactis DSM 27109 and its vector.

2. The use according to claim 1, characterized in that, The chronic pain described is nociplastic pain.

3. The use according to claim 2, characterized in that, The injury-plastic pain is caused by fibromyalgia, irritable bowel syndrome, bladder pain syndrome, complex regional pain syndrome type I, or temporomandibular joint disorder.

4. The use according to claim 2, characterized in that, The injury-plastic pain is characterized by generalized sensitization, functional visceral pain, or regional somatosensory sensitization.

5. The use according to claim 4, characterized in that, The generalized sensitization refers to pain caused by fibromyalgia.

6. The use according to claim 4, characterized in that, The functional visceral pain or the regional somatosensory sensitization is pain caused by irritable bowel syndrome.

7. The use according to claim 1, characterized in that, The amount of at least one pain neurotransmitter was reduced in the subjects.

8. The use according to claim 7, characterized in that, The neurotransmitter is substance P.

9. The use of a composition in the preparation of a medicament for the prevention or treatment of fibromyalgia in a subject with a need, characterized in that, The composition contains an effective amount Lactococcuslactis DSM 27109 and its vector.

10. The use according to claim 9, characterized in that, The subjects showed reduced damage plasticity pain associated with fibromyalgia.

11. The use according to claim 10, characterized in that, The injury-plastic pain is a form of pervasive sensitization.

12. The use according to claim 9, characterized in that, The subjects' depression was improved.

13. The use of a composition in the preparation of a medicament for the prevention or treatment of irritable bowel syndrome in a subject in need, characterized in that, The composition contains an effective amount Lactococcuslactis DSM 27109 and its vector.

14. The use according to claim 13, characterized in that, The subjects showed a reduction in damage plasticity pain associated with irritable bowel syndrome.

15. The use according to claim 14, characterized in that, The aforementioned injury-plastic pain is regional somatosensory sensitization.

16. The use according to claim 13, characterized in that, The amount of substance P decreased in the subjects.

17. The use according to claim 13, characterized in that, Increased production of mucin was observed in the subjects.

18. The use according to claim 13, characterized in that, The intestinal barrier function was enhanced in the subjects.

Images