Role of stem cell factor in the regulation of ICC proliferation and detrusor contraction in rats with an underactive bladder

Low-Intensity Extracorporeal Shock Wave Therapy Ameliorates Detrusor Hyperactivity with Impaired Contractility via Transient Potential Vanilloid Channels: A Rat Model for Ovarian Hormone Deficiency

This study explores low-intensity extracorporeal shock wave therapy (LiESWT)'s efficacy in alleviating detrusor hyperactivity with impaired contractility (DHIC) induced by ovarian hormone deficiency (OHD) in ovariectomized rats. The rats were categorized into the following four groups: sham group; OVX group, subjected to bilateral ovariectomy (OVX) for 12 months to induce OHD; OVX + SW4 group, underwent OHD for 12 months followed by 4 weeks of weekly LiESWT; and OVX + SW8 group, underwent OHD for 12 months followed by 8 weeks of weekly LiESWT. Cystometrogram studies and voiding behavior tracing were used to identify the symptoms of DHIC. Muscle strip contractility was evaluated through electrical-field, carbachol, ATP, and KCl stimulations. Western blot and immunofluorescence analyses were performed to assess the expressions of various markers related to bladder dysfunction. The OVX rats exhibited significant bladder deterioration and overactivity, alleviated by LiESWT. LiESWT modified transient receptor potential vanilloid (TRPV) channel expression, regulating calcium concentration and enhancing bladder capacity. It also elevated endoplasmic reticulum (ER) stress proteins, influencing ER-related Ca2+ channels and receptors to modulate detrusor muscle contractility. OHD after 12 months led to neuronal degeneration and reduced TRPV1 and TRPV4 channel activation. LiESWT demonstrated potential in enhancing angiogenic remodeling, neurogenesis, and receptor response, ameliorating DHIC via TRPV channels and cellular signaling in the OHD-induced DHIC rat model.

Effects of natural products on functional constipation: analysis of active ingredient and mechanism

Constipation is a prevalent clinical ailment of the gastrointestinal system, yet its pathogenesis remains ambiguous. Despite the availability of numerous treatment modalities, they are insufficient in resolving the issue for patients. This work conducted a comprehensive review of the existing literature pertaining to the utilization of natural products for the treatment of constipation, with a focus on the efficacy of natural products in treating constipation, and to provide a comprehensive summary of their underlying mechanisms of action. Upon conducting a thorough review of the extant literature, we found that natural products can effectively treat constipation as modern synthetic drugs and compounded drugs with acetylcholinesterase (AChE) effects, rich in fiber and mucus, and the effects of increasing the tension of the ileum and gastrointestinal tract muscle, mediating signaling pathways, cytokine, excitability of the smooth muscle of the gastrointestinal tract, and regulating the homeostasis of intestinal flora. However, there is a wide variety of natural products, and there are still relatively few studies; the composition of natural products is complex, and the mechanism of action of natural products cannot be clarified. In the future, we need to further improve the detailed mechanism of natural products for the treatment of constipation.

Fenchone Ameliorates Constipation-Predominant Irritable Bowel Syndrome via Modulation of SCF/c-Kit Pathway and Gut Microbiota

In this study we sought to elucidate the therapeutic effects of fenchone on constipation-predominant irritable bowel syndrome (IBS-C) and the underlying mechanisms. An IBS-C model was established in rats by administration of ice water by gavage for 14 days. Fenchone increased the reduced body weight, number of fecal pellets, fecal moisture, and intestinal transit rate, and decreased the enhanced visceral hypersensitivity in the rat model of IBS-C. In addition, fenchone increased the serum content of excitatory neurotransmitters and decreased the serum content of inhibitory neurotransmitters in the IBS-C rat model. Meanwhile, western blot and immunofluorescence experiments indicated that fenchone increased the expressions of SCF and c-Kit. Furthermore, compared with the IBS-C model group, fenchone increased the relative abundance of Lactobacillus, Blautia, Allobaculum, Subdoligranulum, and Ruminococcaceae_UCG-008, and reduced the relative abundance of Bacteroides, Enterococcus, Alistipes, and Escherichia-Shigella on the genus level. Overall, fenchone ameliorates IBS-C via modulation of the SCF/c-Kit pathway and gut microbiota, and could therefore serve as a novel drug candidate against IBS-C.

Helicobacter pylori infection and Parkinson's Disease: etiology, pathogenesis and levodopa bioavailability

Parkinson's disease (PD), a neurodegenerative disorder with an unknown etiology, is primarily characterized by the degeneration of dopamine (DA) neurons. The prevalence of PD has experienced a significant surge in recent years. The unidentified etiology poses limitations to the development of effective therapeutic interventions for this condition. Helicobacter pylori (H. pylori) infection has affected approximately half of the global population. Mounting evidences suggest that H. pylori infection plays an important role in PD through various mechanisms. The autotoxin produced by H. pylori induces pro-inflammatory cytokines release, thereby facilitating the occurrence of central inflammation that leads to neuronal damage. Simultaneously, H. pylori disrupts the equilibrium of gastrointestinal microbiota with an overgrowth of bacteria in the small intestinal known as small intestinal bacterial overgrowth (SIBO). This dysbiosis of the gut flora influences the central nervous system (CNS) through microbiome-gut-brain axis. Moreover, SIBO hampers levodopa absorption and affects its therapeutic efficacy in the treatment of PD. Also, H. pylori promotes the production of defensins to regulate the permeability of the blood-brain barrier, facilitating the entry of harmful factors into the CNS. In addition, H. pylori has been found to induce gastroparesis, resulting in a prolonged transit time for levodopa to reach the small intestine. H. pylori may exploit levodopa to facilitate its own growth and proliferation, or it can inflict damage to the gastrointestinal mucosa, leading to gastrointestinal ulcers and impeding levodopa absorption. Here, this review focused on the role of H. pylori infection in PD from etiology, pathogenesis to levodopa bioavailability.

Alpinia officinarum Hance extract ameliorates diabetic gastroparesis by regulating SCF/c-kit signaling pathway and rebalancing gut microbiota

Diabetic gastroparesis (DGP) is a common complication of type 2 diabetes mellitus (T2DM). Alpinia officinarum Hance (AOH) is one of the most commonly used both as a food and folk medicines, which is rich in diarylheptanoids and flavonoids. The gastroprotection and hypoglycemic effect make AOH has great potential in developing of anti-DGP complementary medicine. However, the molecular mechanisms of AOH that act against DGP are yet to be elucidated. In this study, we evaluated the therapeutic effects, the potential molecular mechanism, and the changes of gut microbiota of AOH in DGP. The 5 components of the AOH were analyzed, and the potential signaling pathway of AOH improving DGP was predicted by molecular docking. Subsequently, DGP rat model was constructed using high-fat-irregular-diet, AOH intervention significantly reduced blood glucose levels, increased gastrointestinal propulsion rate, and improved gastric histological morphology in DGP rats. Meanwhile, AOH has been shown to regulate the SCF/c-kit signaling pathway and rebalance the gut microbiota, which may be closely related to its role in improving DGP. Taken together, AOH may play a protective role on DGP through multiple mechanisms, which might pave the road for development and utilization of AOH.

Combination of fenchone and sodium hyaluronate ameliorated constipation-predominant irritable bowel syndrome and underlying mechanisms

We sought to explore the protective effect of the combination of fenchone (FE) and sodium hyaluronate (SH) on ice water-induced IBS-C rats and the potential mechanism. The neurotransmitter levels, including substance P (SP), motilin (MTL), 5-hydroxytryptamine (5-HT), and vasoactive intestinal peptide (VIP), were determined by ELISA methods. The stem cell factors (SCF)/c-Kit signaling pathway-related protein and mRNA levels were determined by western blot and reverse transcription quantitative polymerase chain reaction (RT-qPCR) analyses, respectively. The expressions of tight ZO-1, Occludin, and Claudin-1 were also measured by western blot assay and immunofluorescence staining. The 16S rRNA gene sequence was used to measure the composition of gut microbiota. The co-administration of FE and SH improved the body weight, number of fecal pellets, fecal moisture, abdominal with drawal reflex score, and gastrointestinal transit rate in IBS-C rats. The unique efficacy of combination depended on the regulation of balance between excitatory and inhibitory neurotransmitters, enhancement of intestinal barrier function, and activation of SCF/c-Kit pathway. The gut microbiota structure was also restored. The ability of FE combined with SH to regulate SCF/c-Kit signaling pathway, enhance intestinal barrier function, and modulate gut microbiota contributes to their efficacy in managing IBS-C in rats.

Underactive Bladder and Detrusor Underactivity: New Advances and Prospectives

Underactive bladder (UAB) is a prevalent but under-researched lower urinary tract symptom that typically occurs alongside detrusor underactivity (DU). Unlike UAB, DU is a urodynamic diagnosis which the International Continence Society (ICS) defines as "a contraction of reduced strength and/or duration, resulting in prolonged bladder emptying and/or a failure to achieve complete bladder emptying within a normal time span". Despite the widespread prevalence of UAB/DU, there are significant gaps in our understanding of its pathophysiological mechanisms, diagnosis, and treatment compared with overactive bladder (OAB) and detrusor overactivity (DO). These gaps are such that clinicians regard UAB/DU as an incurable condition. In recent years, the understanding of UAB has increased. The definition of UAB has been clarified, and the diagnostic criteria for DU have been considered more comprehensively. Meanwhile, a number of non-invasive diagnostic methods have also been reported. Clinical trials involving novel drugs, electrical stimulation, and stem cell therapy have shown promising results. Therefore, this review summarizes recent reports on UAB and DU and highlights the latest advances in their diagnosis and treatment.

Male Lower Urinary Tract Dysfunction: An Underrepresented Endpoint in Toxicology Research

Lower urinary tract dysfunction (LUTD) is nearly ubiquitous in men of advancing age and exerts substantial physical, mental, social, and financial costs to society. While a large body of research is focused on the molecular, genetic, and epigenetic underpinnings of the disease, little research has been dedicated to the influence of environmental chemicals on disease initiation, progression, or severity. Despite a few recent studies indicating a potential developmental origin of male LUTD linked to chemical exposures in the womb, it remains a grossly understudied endpoint in toxicology research. Therefore, we direct this review to toxicologists who are considering male LUTD as a new aspect of chemical toxicity studies. We focus on the LUTD disease process in men, as well as in the male mouse as a leading research model. To introduce the disease process, we describe the physiology of the male lower urinary tract and the cellular composition of lower urinary tract tissues. We discuss known and suspected mechanisms of male LUTD and examples of environmental chemicals acting through these mechanisms to contribute to LUTD. We also describe mouse models of LUTD and endpoints to diagnose, characterize, and quantify LUTD in men and mice.

A Comprehensive Review of the Therapeutic Value of Urine-Derived Stem Cells

Stem cells possess regenerative powers and multidirectional differentiation potential and play an important role in disease treatment and basic medical research. Urine-derived stem cells (USCs) represent a newly discovered type of stem cell with biological characteristics similar to those of mesenchymal stromal cells (MSCs), including their doubling time and immunophenotype. USCs are noninvasive and can be readily obtained from voided urine and steadily cultured. Based on advances in this field, USCs and their secretions have increasingly emerged as ideal sources. USCs may play regulatory roles in the cellular immune system, oxidative stress, revascularization, apoptosis and autophagy. This review summarizes the applications of USCs in tissue regeneration and various disease treatments. Furthermore, by analysing their limitations, we anticipate the development of more feasible therapeutic strategies to promote USC-based individualized treatment.

Therapeutic effect of Cistanche deserticola on defecation in senile constipation rat model through stem cell factor/C-kit signaling pathway

BACKGROUND

Constipation is one of the chronic gastrointestinal functional diseases. It seriously affects the quality of life. Cistanche deserticola (C. deserticola) can treat constipation obviously, but its mechanism has not been clarified. We supposed that mechanism of it improved the intestinal motility by stimulating interstitial Cajal cells (ICC). Activation of the C-kit receptor on the surface of ICC is closely related to ICC function, and the stem cell factor (SCF)/C-kit signaling pathways plays an important role on it. To investigate the mechanism of how C. deserticola treats constipation, this study aimed to establish a constipation model in rats and explore the role of SCF/C-kit signaling pathway in the treatment.

AIM

To explore the SCF/C-kit signaling pathways in the role of C. deserticola for treatment of constipation by a constipation rat model.

METHODS

Forty-eight 8-mo-old Sprague–Dawley rats were divided into 4 groups by random weight method: Normal group (n = 12), model group (n = 12), C. deserticola group (n = 12) and blocker group (n = 12). The normal group received normal saline by gavage; the model group received loperamide by gavage; the blocker group received loperamide and C. deserticola by gavage, and STI571 was injected by intraperitoneally. During treatment, the weight, fecal granules and fecal quality were recorded every 10 d. On day 20 after model induction, the colon tissues of each group were removed. Hematoxylin and eosin staining was used to observe pathological changes. Expression levels of SCF, C-kit and Aquaporin genes were detected by immunohistochemistry, western blotting, and real-time-quantitative polymerase chain reaction. The colonic epithelial mitochondria and goblet cells were observed by transmission electron microscopy.

RESULTS

Compared with the normal group, as treatment progressed, the weight of rats in the model and blocker groups decreased significantly, the stool weight decreased, and the stool quality was dry (P < 0.05). C. deserticola reversed the decrease in body weight and stool weight and improved stool quality. Histopathological analysis indicated that the colonic mucosal epithelium in the model group was incomplete, and the arrangement of the glands was irregular or damaged. Treatment with C. deserticola improved the integrity and continuity of the epithelial cells and regular arrangement of the glands. The blocking agents inhibited the effects of C. deserticola Immunohistochemistry and real-time-quantitative polymerase chain reaction showed that expression of SCF and C-kit protein or genes in the colonic tissue of the model group was decreased (P < 0.05), while treatment with C. deserticola increased protein or gene expression (P < 0.05). Western blotting showed that expression of aquaporin APQ3 was increased, while the expression of Cx43 decreased in the model group. Treatment with C. deserticola inhibited expression of APQ3 and promoted expression of Cx43. Transmission electron microscopy showed that the mitochondria of the colonic epithelium in the model group were swollen and arranged disorderly, and microvilli were sparse. The condition was better in the C. deserticola group. Mice treated with STI571 blocker confirmed that blocking the SCF/C-kit pathway inhibited the improvement of constipation by C. deserticola.

CONCLUSION

C. deserticola improved defecation in rats with constipation, and the SCF/C-kit signaling pathway, which is a key link of ICC function, played an important role of the treatment.

Atractylenolide‑1 alleviates gastroparesis in diabetic rats by activating the stem cell factor/c‑kit signaling pathway

Diabetic gastroparesis (DGP), also known as delayed gastric emptying, is a common complication of diabetes mellitus. There are numerous clinical symptoms associated with DGP, as well as high treatment costs and markedly reduced patient quality of life. However, the pathogenesis of DGP is not clear, thus effective treatment methods are yet to be established. In the present study, a DGP rat model was established in Sprague‑Dawley rats by the intraperitoneal injection of streptozotocin (STZ). DGP model rats were treated with different doses of atractylenolide‑1 to detect alterations in gastrointestinal function, including gastroparesis, gastric emptying, gastric motility, gastric peristalsis and gastric blood flow. Compared with the DGP group, atractylenolide‑1 treatment significantly reduced glycaemia and the level of glycated hemoglobin, as well as restoring gastrointestinal function. Gastroparesis, gastric emptying, gastric motility, gastric peristalsis and gastric blood flow were significantly impaired in the STZ‑induced group compared with the vehicle control group. Moreover, the STZ‑induced group displayed downregulated expression levels of the DGP indicator KIT proto‑oncogene, receptor tyrosine kinase (c‑kit), as investigated by immunohistochemistry, and stem cell factor (SCF) protein, as assessed using ELISA, significantly enhanced rat interstitial cells of Cajal (ICC) apoptosis, and significantly altered levels of oxidative stress‑related markers (malondialdehyde and superoxide dismutase) in the serum and gastric tissues compared with the vehicle control group. By contrast, treatment with atractylenolide‑1 significantly counteracted the effects of DGP on peristalsis, inhibited apoptosis and suppressed oxidative stress by regulating the expression of heme oxygenase 1 in STZ‑induced DGP model rats. Further research indicated that atractylenolide‑1 regulated oxidative stress reactions and improved gastric function by activating the SCF/c‑kit signaling pathway. Collectively, the results of the present study suggested that atractylenolide‑1 promoted ICC survival and preserved the structure of the gastric tissue network in a DGP rat model via the SCF/c‑kit signaling pathway, providing novel insights for the treatment of DGP.

Helicobacter pylori causes delayed gastric emptying by decreasing interstitial cells of Cajal

Helicobacter pylori (HP) infection is one of the most frequent bacterial infections in humans and is associated with the pathogenesis of gastric motility disorders such as delayed gastric emptying (DGE). Although HP infection is considered to delay gastric emptying, there has been little research on the underlying mechanism. Gastric motility involves interactions among gastrointestinal hormones, smooth muscle, enteric and extrinsic autonomic nerves and interstitial cells of Cajal (ICCs), and ICCs play an important role in gastrointestinal motility. Mutation or loss of stem cell factor (SCF) expression is known to reduce the number of ICCs or alter the integrity of the ICC network, contributing to gastrointestinal dysmotility. The aim of the present study was to investigate whether a reduction in ICCs contributes to the DGE caused by HP. A mouse model of HP infection was established and gastric emptying was compared between HP-infected and uninfected mice using the bead method. In addition, ICC counts and SCF expression levels in gastric tissue were evaluated using immunohistochemistry and western blotting, respectively. The results revealed that gastric emptying was significantly slower, the number of ICCs in gastric tissue was significantly reduced and the protein level of SCF in gastric tissue was significantly decreased in HP-infected mice compared with uninfected mice. Therefore, it may be concluded that HP reduced the number of ICCs by decreasing the expression of SCF protein in gastric tissue, thereby causing DGE.

Pathogenesis evidence from human and animal models of detrusor underactivity

Detrusor underactivity (DU) is a common urodynamic diagnosis in patients with lower urinary tract symptoms and large post-voiding residual volume. Animal and human studies showed the possible etiologies of DU include central or peripheral nerve injury, bladder outlet obstruction, chronic ischemia, aging, diabetes mellitus, and sympathetic inhibition of micturition reflex. Evidence from animal and human DU studies with various etiologies revealed highly similar gross and histological characteristics in the bladders, including increased bladder weight, bladder wall thickening, inflammation, collagen deposition, and fibrosis. In electron microscopy, smooth muscle destruction, swollen mitochondria, decreased nerve innervation, caveolae, and umbrella cell fusiform vesicles were noted in the DU bladders. Most animal DU models demonstrate detrusor contractility changes from compensatory to the decompensatory stage, and the change was compatible with human DU observation. The cystometry in the DU animal studies is characterized by impaired contractility, prolong intercontraction interval, and hyposensation, while in vitro bladder muscle strips experiment may exhibit normal detrusor contractility. Decreased bladder blood flow and increased oxidative stress in bladders had been proved in different animal DU models, suggesting they should be important in the DU pathogenesis pathway. Sensory receptors mRNA and protein expression changes in DU bladders had been observed in both animal and human studies, including muscarinic receptors M2, M3, adrenergic receptor β3, purinergic receptor P2X1, P2X3, and transient receptor potential vanilloid (TRPV) 1 and TRPV4. Although some of the sensory receptors changes remain controversial, it might be the target for further pharmacologic treatments.

Prophylactic Effect of Lactobacillus plantarum YS4 on Oxazolone-Induced Colitis in BALB/c Mice

In the present research, the effects of Lactobacillus plantarum YS4 (LP-YS4) on colitis were tested in an oxazolone-induced mouse model. BALB/c mice were induced by oxazolone and then treated with LP-YS4. The serum levels of mice were analyzed using commercial kits and the protein and mRNA expression levels of mouse colon tissue were detected by Western blotting and qPCR assay, respectively. The results demonstrated that LP-YS4 significantly (P < 0.05) increased the colon length and ratio of colon weight/length in mice with colitis and attenuated the negative effects of colitis. The results also showed that treatment with LP-YS4 significantly reduced the serum concentrations of ET-1, SP, and IL-10 while significantly increasing those of SS, VIP, and IL-2 in colitis mice (P < 0.05). In addition, LP-YS4 significantly increased the activities of GSH and SOD while decreasing those of MPO and MDA in the colon tissue of colitis mice (P < 0.05). LP-YS4 also significantly upregulated the mRNA and protein expression of c-Kit, eNOS, nNOSe, and SCF in colitis mice while significantly downregulating the relative expression of iNOS. In summary, LP-YS4 could reduce the negative effects of colitis, and such effects were better than those of the common probiotic Lactobacillus bulgaricus.

Management of Urinary Incontinence With Underactive Bladder: A Review

Urinary incontinence is caused by storage function failure, while underactive bladder (UAB) is caused by a decline in detrusor contractility and voiding dysfunction. As the treatment mechanisms for incontinence and UAB are contrary to each other, it is difficult to treat both incontinence and UAB, and the patient’s quality of life can be further degraded. Conventional midurethral sling (MUS), such as transobturator tape or retropubic MUS, introduces a risk of postoperative voiding dysfunction in stress urinary incontinence with UAB. However, there have been several reports about the efficacy and safety of conventional MUS. Adjustable sling procedures, such as transobturator adjustable tape or the Remeex system, have better outcomes than conventional MUS because they control tension both during and after surgery. When voiding dysfunction occurs after incontinence treatment with UAB, voiding symptoms can be improved by various therapeutic modalities. Clean intermittent catheterization is recommended for patients with significant increased postvoid residual volumes or urinary retention. Although pharmacotherapy such as with alpha-blockers or parasympathomimetics can be considered for UAB, there is insufficient evidence of their effect on incontinence with UAB. Future therapies, such as stem cell therapy or gene therapy, may be used to treat incontinence with UAB. The possibility of management urgency urinary incontinence that related to detrusor hyperactivity with impaired contractility using sacral neuromodulation has been suggested. Further research is needed to establish evidence for the efficacy and safety of treatments for incontinence with UAB and improve patient quality of life.

Differentiation of human urine-derived stem cells into interstitial cells of Cajal-like cells by exogenous gene modification: A preliminary study

Human urine-derived stem cells (hUSCs) show multipotential differentiation ability and can differentiate into mesodermal cell lineages. Interstitial cells of Cajal-like cells (ICC-LCs) are crucial for the pace-making function of spontaneous contraction in the bladder. However, the mechanisms by which hUSCs generate ICC-LCs have not been elucidated. In this study, we developed a strategy for directional differentiation of hUSCs into ICC-LCs. hUSCs were transfected with lentiviral vectors encoding c-Kit, stem cell factor (SCF), hyperpolarization activated cyclic nucleotide gated potassium channel 4 (HCN4), and 5-azacytidine induced 2 (AZI2) genes, and the cells were cultured for an additional 7 days in specific medium. The expression of the surface marker c-Kit on ICC-LCs was determined at 7 days after transfection. hUSCs were successfully expanded and transfected with the four lentiviral vectors. hUSCs transfected with lentiviral-c-Kit, lentiviral-HCN4, and lentiviral-AZI2 showed higher expression of c-Kit 7 days after transfection, but only the lentiviral-HCN4-transfected cells showed morphological alterations in ICC-LCs. These cells also displayed visible HCN current amplitude and density. This approach may provide a new strategy for the treatment of underactive bladder.