Evaluation of the hypoglycemic effect of probiotics via directly consuming glucose in intestines of STZ-induced diabetic mice and glucose water-induced diabetic mice

Low-Molecular-Weight Compounds Produced by the Intestinal Microbiota and Cardiovascular Disease

Cardiovascular disease is the main cause of mortality in industrialized countries, with over 500 million people affected worldwide. In this work, the roles of low-molecular-weight metabolites originating from the gut microbiome, such as short-chain fatty acids, hydrogen sulfide, trimethylamine, phenylacetic acid, secondary bile acids, indoles, different gases, neurotransmitters, vitamins, and complex lipids, are discussed in relation to their CVD-promoting or preventing activities. Molecules of mixed microbial and human hepatic origin, such as trimethylamine N-oxide and phenylacetylglutamine, are also presented. Finally, dietary agents with cardioprotective effects, such as probiotics, prebiotics, mono- and poly-unsaturated fatty acids, carotenoids, and polyphenols, are also discussed. A special emphasis is given to their gut microbiota-modulating properties.

Probiotics for pancreatic β-cell function: from possible mechanism of action to assessment of effectiveness

Type 2 diabetes (T2D) is a metabolic disease characterized by chronic hyperglycemia because of insulin resistance (IR) and\or pancreatic β-cell dysfunction. Last century research showed that gut microbiota has a direct effect on metabolism and metabolic diseases. New studies into the human microbiome and its connection with the host is making it possible to develop new therapies for a wide variety of diseases. Inflammation is a well-known precursor to metabolic syndrome, which increases the risk of hypertension, visceral obesity, and dyslipidemia, which can lead to T2D through the damage of pancreatic β-cell and reduce insulin secretion. Current understanding for beneficial effects of probiotics in T2D strictly rely on both animal and clinical data, which mostly focused on their impact on IR, anthropometric parameters, glycemic control and markers of chronic systemic inflammation. From the other hand, there is a lack of evidence-based probiotic efficacy on pancreatic β-cell function in terms of T2D and related metabolic disorders. Therefore, current review will focus on the efficacy of probiotics for the protection of β-cells damage and it`s mechanism in patients with T2D.

Gut microbiota interventions in type 2 diabetes mellitus: An umbrella review of glycemic indices

BACKGROUND

We aimed to explore how probiotics, prebiotics, or synbiotics impact glycemic indices in patients with diabetes mellitus.

METHOD

A comprehensive search was conducted on PubMed, Scopus, and Web of Science from inception up to April 2023. The random-effects model was employed for the study analysis. Furthermore, sensitivity and subgroup analyses were conducted to investigate potential sources of heterogeneity. AMSTAR2 checklist was used to determine the quality of studies. Comprehensive meta-analysis version 3 was used for the study analysis.

RESULT

A total of 31 studies were included in the final analysis. Based on the results of the meta-analysis, gut microbial therapy could significantly decrease serum fasting blood glucose levels in patients with type 2 diabetes mellitus (effect size: -0.211; 95 % CI: -0.257, -0.164; P < 0.001). Additionally, significant associations were also found between gut microbial therapy and improved serum levels of fasting insulin, glycated hemoglobin, and homeostatic model assessment for insulin resistance (effect size: -0.087; 95 % confidence interval: -0.120, -0.053; P < 0.001; effect size: -0.166; 95 % confidence interval: -0.200, -0.132; P < 0.001; effect size: -0.230; 95 % confidence interval: -0.288, -0.172; P < 0.001, respectively).

CONCLUSION

Our results revealed promising effects of gut microbiota modulation on glycemic profile of patients with type 2 diabetes mellitus. The use of these agents as additional treatments can be considered.

Psychobiotics Lactiplantibacillus plantarum JYLP-326: Antidepressant-like effects on CUMS-induced depressed mouse model and alleviation of gut microbiota dysbiosis

BACKGROUND

Depression affects a significant portion of the global population and has emerged as one of the most debilitating conditions worldwide. Recent studies have explored the relationship between depression and the microbiota of the intestine, revealing potential avenues for effective treatment.

METHODS

To evaluate the potential alleviation of depression symptoms, we employed a depression C57BL/6 mice model induced by chronic unpredictable mild stress (CUMS). We administered Lactiplantibacillus plantarum JYLP-326 and conducted various animal behavior tests, including the open-field test (OFT), sucrose preference test (SPT), and tail-suspension test (TST). Additionally, we conducted immunohistochemistry staining and analyzed the hippocampal and colon parts of the mice.

RESULTS

The results of the behavior tests indicated that L. plantarum JYLP-326 alleviated spontaneous behavior associated with depression. Moreover, the treatment led to significant improvements in GFAP and Iba1, suggesting its potential neuroprotective effects. Analysis of the hippocampal region indicated that L. plantarum JYLP-326 administration upregulated p-TPH2, TPH2, and 5-HT1AR, while downregulating the expression of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. In the colon, the treatment inhibited the TLR4-MyD88-NF-κB pathway and increased the levels of occludin and ZO-1, indicating improved intestinal barrier function. Additionally, the probiotic demonstrated a regulatory effect on the HMGB1-RAGE-TLR4 signaling pathway.

CONCLUSIONS

Our findings demonstrate that L. plantarum JYLP-326 exhibits significant antidepressant-like effects in mice, suggesting its potential as a therapeutic approach for depression through the modulation of gut microbiota. However, further investigations and clinical trials are required to validate its safety and efficacy for human use.

Induced acute hyperglycemia modifies the barrier function of the intestinal epithelium by tissue inflammation and tight junction disruption resulting in hydroelectrolytic secretion in an animal model

Diabetic-metabolic syndrome (MetS-D) has a high prevalence worldwide, in which an association with the rupture of the intestinal epithelium barrier function (IEBF) has been pointed out, but the functional and morphological properties are still not well understood. This study aimed to evaluate the impact of acute hyperglycemia diabetes on intestinal tight junction proteins, metabolic failure, intestinal ion and water transports, and IEBF parameters. Diabetes was induced in male Rattus norvegicus (200-310 g) with 0.5 mL of streptozotocin (70 mg/kg). Glycemic and clinical parameters were evaluated every 7 days, and intestinal parameters were evaluated on the 14th day. The MetS-D animals showed a clinical pattern of hyperglycemia, with increases in the area of villi and crypts, lactulose:mannitol ratio, myeloperoxidase (MPO) activity, and intestinal tissue concentrations of malondialdehyde (MDA), but showed a reduction in reduced glutathione (GSH) when these parameters were compared to the control. The MetS-D group had increased secretion of Na+, K+, Cl-, and water compared to the control group in ileal tissue. Furthermore, we observed a reduction in mRNA transcript of claudin-2, claudin-15, and NHE3 and increases of SGLT-1 and ZO-1 in the MetS-D group. These results showed that MetS-D triggered intestinal tissue inflammation, oxidative stress, complex alterations in gene regulatory protein transcriptions of intestinal transporters and tight junctions, damaging the IEBF and causing hydroelectrolyte secretion.

Probiotics, prebiotics, and postbiotics in health and disease

The gut microbiota and its homeostasis play a crucial role in human health. However, for some diseases related to the gut microbiota, current traditional medicines can only relieve symptoms, and it is difficult to solve the root causes or even cause side effects like disturbances in the gut microbiota. Increasing clinical studies and evidences have demonstrated that probiotics, prebiotics, and postbiotics can prevent and treat various diseases, but currently they can only be used as dietary supplements rather than medicines, which restricts the application of probiotics in the field of medicine. Here, this review analyzes the importance of gut microbiota in human health and the current problems of traditional medicines, and systematically summarizes the effectiveness and mechanisms of probiotics, prebiotics, and postbiotics in maintaining health and treating diseases based on animal models and clinical trials. And based on current research outcomes and development trends in this field, the challenges and prospects of their clinical application in maintaining health, alleviating and treating diseases are analyzed. It is hoped to promote the application of probiotics, prebiotics, and postbiotics in disease treatment and open up new frontiers in probiotic research.

Exploration of Antidiabetic, Cholesterol-Lowering, and Anticancer Upshot of Probiotic Bacterium Pediococcus pentosaceus OBK05 Strain of Buttermilk

Chronic metabolic disorders such as hyperglycemia (diabetes), hyperlipidemia (high cholesterol), and cancer have become catastrophic diseases worldwide. Accordingly, probiotic intervention is a new approach for alleviating catastrophic diseases. In the present study, Pediococcus pentosaceus OBK05 was investigated as a potential probiotic bacterium for antidiabetic, cholesterol-lowering, and anticancer activities by in vitro and in vivo studies. Cell-free supernatant (CFS) of OBK05 showed potent antidiabetic activity by inhibition of α-amylase (72 ± 0.9%) and α-glucosidase (61 ± 0.8%) activity in vitro when compared to that of acarbose as standard (86 ± 0.9%). Furthermore, the in vivo cholesterol-lowering activity of OBK05 was studied using cholesterol-fed hypercholesterolemic mice. When compared to the cholesterol-fed group, the OBK05-intervened cholesterol-fed mice group had significantly lowered the levels of lipids and showed significantly lower lipid droplet accumulation in the histology of hepatocytes. Similarly, CFS exhibited higher anticancer activity (87.57 ± 1.27%) against HT-29 cells with an IC50 of 54.51 ± 1.8. Fluorescence-activated cell sorting (FACS) analysis revealed that CFS induced the cell cycle arrest by inhibiting the G1 to S phase transition. Further, in vivo anticancer activities were confirmed in BALB/c mice models, which were divided into four groups and held for 16 weeks. HT-29 cells (5×109/mice) were injected subcutaneously twice (0 and 2nd week), and OBK05 (3 ×105 CFU/mL) was given orally to the respective groups. The OBK05-intervened HT-29 cell-induced mice group showed significant improvement at the histological level and alleviated the degree of atypia in the intestine.

Neuroprotective effects of an engineered Escherichia coli Nissle 1917 on Parkinson's disease in mice by delivering GLP-1 and modulating gut microbiota

Considerable evidence suggests that insulin resistance is closely linked to Parkinson's disease (PD), leading to agents aiming at treating diabetes can be regarded as new neuroprotective strategies in PD, notably glucagon-like peptide-1 (GLP-1). However, the extremely short half-life of GLP-1 due to degradation by the ubiquitous proteolytic enzyme limits its clinical application. In this study, we engineered the recombinant integrant probiotic strain Escherichia coli Nissle 1917 (EcN) to create a strain EcN-GLP-1 that effectively delivers the heterologous GLP-1 molecule. Subsequently, we assessed its neuroprotective effects on 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced PD mice. We demonstrated that EcN-GLP-1 treatment could improve motor deficits, increase tyrosine hydroxylase-positive neurons, suppress microglia and astrocyte activation, reduce brain and colon inflammation, and ameliorate colonic barrier function damaged by MPTP induction. Meanwhile, we confirmed that the oral administration of EcN-GLP-1 could restore the disturbance of gut microbiota in the MPTP-induced PD mice, by reducing the relative abundances of Akkermansia and Oscillospira, and increasing the level of Prevotella in the gut. These results support further development of an engineered probiotic platform in which production of GLP-1 for gut-brain disorders, such as PD.

Improvement effect of a next-generation probiotic L. plantarum-pMG36e-GLP-1 on type 2 diabetes mellitus via the gut-pancreas-liver axis

Next-generation probiotics (NGPs) are currently being investigated as therapeutic agents that impact the gut microbiota and disease development. Glucagon-like peptide-1 (GLP-1) shows an excellent therapeutic effect on diabetes, but has an extremely short half-life in vivo. Here, we constructed a novel and diabetes-specific NGP, the genetically engineered strain Lactobacillus plantarum (L. plantarum)-pMG36e-GLP-1, and evaluated its ameliorative effect on type 2 diabetes mellitus (T2DM) in artificially induced mice and transgenic mice. In vitro, L. plantarum-pMG36e-GLP-1 showed good genetic stability and probiotic characteristics. In the high-fat diet combined with streptozotocin (HFD/STZ)-induced T2DM mice, L. plantarum-pMG36e-GLP-1 relieved the diabetic symptoms, regulated the intestinal microbiota, and reduced the inflammatory reaction in the pancreatic tissue. Meanwhile, the apoptosis of pancreatic islet cells was inhibited, while islet tissue morphology repairs, islet β-cell proliferation, and insulin secretion were all promoted by L. plantarum-pMG36e-GLP-1. Furthermore, a similar effect of the engineered strain on diabetic symptoms and the pancreas was observed in db/db mice, and the metabolism of lipids in the liver was regulated. Together, the findings of this study confirmed the anti-hyperglycemic effect of the engineered strain L. plantarum-pMG36e-GLP-1, providing a promising approach for T2DM treatment.

Psychobiotic interventions attenuate chronic alcohol use-mediated exacerbation of posttraumatic stress disorder in rats: the role of gut-liver axis response

OBJECTIVES

The incidence of co-occurring alcohol-use disorder (AUD) and post-traumatic stress disorder (PTSD) is high, and the presence of one disorder aggravates the severity of the other. Emerging evidence shows the neuroprotective and anti-inflammation functions of psychobiotics. Hence, the study explored the effects of probiotics and synbiotic inulin on the gut- and liver-oxidative and inflammatory biomarkers in chronic alcohol exacerbation of PTSD symptoms in rats.

METHODS

Young adult rats were administered 10% ethanol in a two-bottle choice test for six weeks and were subjected to single prolonged stress. Probiotics and synbiotic intervention followed this. Markers of oxido-inflammatory stress, liver functions, intestinal (faecal) metabolites, occludin expression, and histopathology of the ileum and liver were evaluated.

RESULTS

Chronic alcohol drinking and PTSD increased oxido-inflammatory stress, markers of hepatic damage, and reduced faecal metabolites, which were attenuated by probiotic and synbiotic interventions. Furthermore, reduced immunoexpression of gut and liver occludin, with loss of barrier integrity, viable hepatocytes, congestive portal area, and shortened villi and crypt depth, were observed. Probiotic and synbiotic interventions mitigated these effects.

CONCLUSIONS

The study demonstrates that psychobiotics mitigate the detrimental effects of co-occurring chronic alcohol intake in the context of PTSD.

Lactobacillus-fermented yogurt exerts hypoglycemic, hypocholesterolemic, and anti-inflammatory activities in STZ-induced diabetic Wistar rats

Hyperglycemia is a symptom of type 2 diabetes mellitus, a chronic metabolic disease characterized by elevated blood glucose concentrations. Antidiabetic drugs are common treatments for this metabolic disorder; however, they may have unpleasant side effects. This study hypothesized that probiotic fermented products could preserve nutritional value, maintain metabolic homeostasis, and attenuate the inflammatory response associated with diabetes while reducing side effects. Lactobacillus plantarum KU985438 and Lactobacillus rhamnosus KU985439 showed the lowest alfa-amylase enzyme (α-amylase) activity among 8 lactobacilli tested. These 2 strains were used to develop functional fermented milk products, and their antidiabetic efficacy was tested in induced diabetic Wistar rats. The treatment of diabetic rats with L. plantarum KU985438 or L. rhamnosus KU985439 fermented yogurt resulted in a considerable reduction in blood glucose concentrations (136.79% and 145.17%, respectively) and α-amylase concentrations (56.84% and 56.84%, respectively) compared with conventional treatments. Diabetes relief began after 4 days of yogurt consumption compared with drug-based treatment. Significant improvements in both liver and kidney enzyme concentrations were also observed, in addition to a significant increase in high-density lipoprotein cholesterol concentrations and improved lipid profiles. Inhibition in nuclear factor κB and an increase in Bcl-2 concentrations were also detected. Histopathological examination of both hepatic and pancreatic cells revealed the positive effects of the studied treatment compared with standard treatment. Therefore, the selected Lactobacilli, which has hypoglycemic potential, could be used to produce functional nutraceutical antidiabetic supplements.

Probiotic Mechanisms Affecting Glucose Homeostasis: A Scoping Review

The maintenance of a healthy status depends on the coexistence between the host organism and the microbiota. Early studies have already focused on the nutritional properties of probiotics, which may also contribute to the structural changes in the gut microbiota, thereby affecting host metabolism and homeostasis. Maintaining homeostasis in the body is therefore crucial and is reflected at all levels, including that of glucose, a simple sugar molecule that is an essential fuel for normal cellular function. Despite numerous clinical studies that have shown the effect of various probiotics on glucose and its homeostasis, knowledge about the exact function of their mechanism is still scarce. The aim of our review was to select in vivo and in vitro studies in English published in the last eleven years dealing with the effects of probiotics on glucose metabolism and its homeostasis. In this context, diverse probiotic effects at different organ levels were highlighted, summarizing their potential mechanisms to influence glucose metabolism and its homeostasis. Variations in results due to different methodological approaches were discussed, as well as limitations, especially in in vivo studies. Further studies on the interactions between probiotics, host microorganisms and their immunity are needed.

An insight into the health beneficial of probiotics dairy products: a critical review

Probiotic dairy products satisfy people's pursuit of health, and are widely favored because of their easy absorption, high nutritional value, and various health benefits. However, its effectiveness and safety are still controversial. This proposal aims to analyze the effect of probiotics on the quality characteristics of dairy products, clarify a series of physiological functions of probiotic dairy products and critically evaluate the effectiveness and safety of probiotic dairy products. Also, dairy products containing inactivated microorganisms were compared with probiotic products. The addition of probiotics enables dairy products to obtain unique quality characteristics, and probiotic dairy products have better health-promoting effects. This review will promote the further development of probiotic dairy products, provide directions for the research and development of probiotic-related products, and help guide the general public to choose and purchase probiotic fermentation products.

Protective effect of nimbolide against streptozotocin induced gestational diabetes mellitus in rats via alteration of inflammatory reaction, oxidative stress, and gut microbiota

BACKGROUND

Gestational diabetes mellitus (GDM) is a significant pregnancy-related condition, which showed effect on the development of fetal. Anti-inflammatory and antioxidant therapy commonly used for the treatment of GDM. Nimbolide already confirmed their anti-inflammatory and anti-oxidant effect against various animal disease model. Our objective in this research is to investigate the protective effect of nimbolide against STZ induced GDM and elucidate the mechanism.

METHODS

In this experimental study, pregnant female Wistar rats were used and STZ (40 mg/kg) was used to induce the GDM. Blood glucose level (BGL), body weight and plasma insulin were assessed at regular time (gestational day 0, 9, and 18). Water intake, food intake, fecal and urine output were also estimated. In the female rats, hemoglobin (Hb), glycalated hemoglobin (HbA1c), hepatic glycogen, fructosamine, adiponectin, leptin, lipid, antioxidant and inflammatory cytokines parameters were estimated. In the fetuses, the fetues weight, implementation loss, and fetal weight were estimated. At the completion of the protocol, biochemical parameters were calculated. Gut microbiota was estimated in end of the study.

RESULTS

Nimbolide treatment significantly (p < .001) improved the fetuses level and suppressed the fetal weight and implantation loss. Nimbolide treatment significantly (p < .001) suppressed the BGL and enhanced the body weight, insulin level. Nimbolide treatment suppressed the water intake, food intake, urinary and fecal output. Nimbolide significantly (p < .001) suppressed the fructosamine, leptin and enhanced the adiponectin level. Nimbolide treatment significantly (p < .001) decreased the malonaldehyde (MDA) level and boosted the total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione S-transferase (GST) and catalase (CAT); suppressed the level of TNF-α, IL-1β, IL-6, and boosted the level of IL-10. Furthermore, nimbolide treatment reversed the gut microbiota alteration induced via STZ in female rats. At the phylum level, the Firmicutes and Bacteroidetes relative abundance was altered via nimbolide treatment. The ratio of F/B boosted in GDM group and nimbolide treatment significantly (p < .001) suppressed. Nimbolide considerably suppressed the firmicutes and enhanced the Bacteroidetes, CAG-352, Lacnospirace.

CONCLUSION

Based on the findings, we may conclude that nimbolide protects the pregnant rats from GDM via alteration of inflammation, oxidative stress, and gut microbiota.

Engineered Bacteria EcN-MT Alleviate Liver Injury in Cadmium-Exposed Mice via its Probiotics Characteristics and Expressing of Metallothionein

Cadmium (Cd) exposure is a widespread problem in many parts of the world, but effective means to treat Cd exposure is still lacking. Hence, an engineered strain expressing metallothionein (MT) named Escherichia coli Nissle 1917 (EcN)-MT was constructed, and its potential in the treatment of Cd exposure was evaluated. The in vitro studies showed that metallothionein expressed by EcN-MT could significantly bind Cd. Further, the in vivo results indicated that EcN-MT strain could reduce 26.3% Cd in the liver and increase 24.7% Cd in the feces, which greatly decreased malondialdehyde (MDA) levels and increased catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD) levels in liver, and reduced the expression of toll-like receptor4 (TLR4), nuclear factor-κB (NF-κB), the myeloid differentiation factor 88 (Myd88) andincreased B-cell lymphoma 2 (Bcl-2)/Bcl-2-Associated X (Bax). Moreover, high throughput sequencing results indicated that EcN-MT strain greatly enhanced the beneficial bacteria of Ruminococcaceae, Lactobacillaceae, Akkermansia, Muribaculaceae, Lachnospiraceae, Dubosiella and restored the disturbed microbial ecology to the normal level. Therefore, the high Cd binding capacity of the expressed metallothionein, together with the beneficial characteristics of the host bacteria EcN, makes EcN-MT a sound reagent for the treatment of subchronic Cd exposure-induced liver injury.

Oral Administration of Bacterial β Cell Expansion Factor A (BefA) Alleviates Diabetes in Mice with Type 1 and Type 2 Diabetes

Diabetes mellitus (DM) is a group of metabolic diseases, and there is an urgent need to develop new therapeutic DM oral drugs with fewer side effects and sound therapeutic efficacy. In this study, a β cell expansion factor A (BefA) production strain of Escherichia coli (BL21-pet 28C-BefA) was constructed, and the antidiabetes effect of BefA was evaluated using type 1 DM (T1DM) and type 2 DM (T2DM) mice models. The T1DM mice results indicated that BefA significantly reduced blood glucose levels; exerted a protective effect on islet β cell morphology; downregulated the expressions of TLR-4, p-NFκB/NFκB, and Bax/Bcl-2, and the secretion levels of IL-1β and TNF-α; increased the expression of PDX-1 protein and insulin secretion in a concentration-dependent manner; and restored the disturbed microbial diversity to normal levels. Similarly with the T1DM mice, BefA obviously increased islet β cells and reduced the inflammatory reaction and apoptosis in T2DM mice, as well as improved liver lipid metabolism by downregulating the expressions of CEBP-α, ACC, and Fasn; inhibited the synthesis of triglycerides; and induced Cpt-1, Hmgcs2, and Pparα in a concentration-dependent manner. In conclusion, BefA alleviates diabetes via increasing the number of islet β cells, reducing the inflammatory reaction and apoptosis, improving liver lipid metabolism, and restoring microbial diversity to normal levels, which provides a new strategy for a DM oral drug.

Lactobacillus acidophilus NX2-6 Improved High-Fat Diet-Induced Glucose Metabolism Disorder Independent of Promotion of Insulin Secretion in Mice

High-fat diet (HFD) contributes to metabolic inflammation and glucose metabolism disorder, thereby resulting in the pathogenesis of metabolic syndrome. Accumulating evidence has revealed that some probiotics could improve HFD-induced metabolic inflammation and glucose metabolism disorder. Our previous study has discovered that Lactobacillus acidophilus NX2-6 exhibited in vitro lipid-lowering, antioxidative, and anti-inflammatory activities. This study mainly investigated whether L. acidophilus NX2-6 improved HFD-induced glucose metabolism disorder. The results exhibited that L. acidophilus NX2-6 effectively reduced blood glucose levels and improved glucose tolerance by activating the insulin signaling pathway, promoting glucose uptake, glycolysis, and intestinal gluconeogenesis and suppressing hepatic gluconeogenesis, independent of regulation of glycogen synthesis in the liver and muscle. Enhanced insulin sensitivity was associated with L. acidophilus NX2-6-mediated suppression of inflammatory cascades in the target organs. Meanwhile, L. acidophilus NX2-6 also improved hepatic energy metabolism via the FGF21/AMPKα/PGC-1α/NRF1 pathway. However, L. acidophilus NX2-6 did not affect apoptosis, pyroptosis, inflammation, and endoplasmic reticulum stress in the pancreas of HFD-fed mice. In conclusion, our results indicated that L. acidophilus NX2-6 improved glucose metabolism disorder through enhancing insulin sensitivity, suppressing metabolic inflammation, and promoting energy expenditure.

Streptozotocin-Induced Diabetes in a Mouse Model (BALB/c) Is Not an Effective Model for Research on Transplantation Procedures in the Treatment of Type 1 Diabetes

Type 1 diabetes (T1D) is characterized by the destruction of over 90% of the β-cells. C-peptide is a parameter for evaluating T1D. Streptozotocin (STZ) is a standard method of inducing diabetes in animals. Eight protocols describe the administration of STZ in mice; C-peptide levels are not taken into account. The aim of the study is to determine whether the STZ protocol for the induction of beta-cell mass destruction allows for the development of a stable in vivo mouse model for research into new transplant procedures in the treatment of type 1 diabetes. Materials and methods: Forty BALB/c mice were used. The animals were divided into nine groups according to the STZ dose and a control group. The STZ doses were between 140 and 400 mg/kg of body weight. C-peptide was taken before and 2, 7, 9, 12, 14, and 21 days after STZ. Immunohistochemistry was performed. The area of the islet and insulin-/glucagon-expressing tissues was calculated. Results: Mice who received 140, 160, 2 × 100, 200, and 250 mg of STZ did not show changes in mean fasting C-peptide in comparison to the control group and to day 0. All animals with doses of 300 and 400 mg of STZ died during the experiment. The area of the islets did not show any differences between the control and STZ-treated mice in groups below 300 mg. The reduction of insulin-positive areas in STZ mice did not exceed 50%. Conclusions: Streptozotocin is not an appropriate method of inducing a diabetes model for further research on transplantation treatments of type 1 diabetes, having caused the destruction of more than 90% of the β-cell mass in BALB/c mice.

Evaluation of hypoglycemic effect, safety and immunomodulation of Prevotella copri in mice

The gut bacterium Prevotella copri (P. copri) has been shown to lower blood glucose levels in mice as well as in healthy humans, and is a promising candidate for a next generation probiotic aiming at prevention or treatment of obesity and type 2 diabetes. In this study the hypoglycemic effect of live P. copri was confirmed in mice and pasteurization of P. copri was shown to further enhance its capacity to improve glucose tolerance. The safety of live and pasteurized P. copri was evaluated by a 29-day oral toxicity study in mice. P. copri did not induce any adverse effects on body growth. General examination of the mice, gross pathological and histological analysis showed no abnormalities of the vital organs. Though relative liver weights were lower in the pasteurized (4.574 g ± 0.096) and live (4.347 g ± 0.197) P. copri fed groups than in the control mice (5.005 g ± 0.103) (p = 0.0441 and p = 0.0147 respectively), no liver biochemical marker aberrations were detected. Creatinine serum levels were significantly lower in mice fed with live (p = 0.001) but not pasteurized (p = 0.163) P. copri compared to those of control mice. Haematological parameter analysis and low plasma Lipopolysaccharide Binding Protein (LBP) levels ruled out systemic infection and inflammation. Immunomodulation capacity by P. copri as determined by blood plasma cytokine analysis was limited and gut colonisation occurred in only one of the 10 mice tested. Taken together, no major adverse effects were detected in P. copri treated groups compared to controls.

Enhanced In Vitro Functionality and Food Application of Lactobacillus acidophilus Encapsulated in a Whey Protein Isolate and (-)-Epigallocatechin-3-Gallate Conjugate

The present study investigated the potential of free radical grafting conjugation of whey protein isolate (WPI) and (-)-epigallocatechin-3-gallate (EGCG), followed by freeze-drying, for the safe delivery of probiotic Lactobacillus acidophilus (LA) upon digestion and in food systems. WPI-EGCG-LA microspheres presented higher encapsulation efficiency (97%) than native WPI-LA (70%) and maltodextrin (MD-LA 75%). The physicochemical characteristics of all microspheres, including moisture content, water activity, and hygroscopicity, were within the acceptable range for the stability of industrial powders. Scanning electron microscopy of WPI-EGCG-LA revealed a glass-like structure, with a smoother and less porous surface area than WPI-LA and MD-LA, as a result of the strong binding affinity between WPIs and EGCG. Particle sizes ranged from 438.4 to 453.3 μm. The structural stability of WPI-EGCG-LA was further confirmed by Fourier transform infrared spectra, which revealed some changes in the protein secondary structure. Thermogravimetric and differential scanning calorimetry analysis showed that WPI-EGCG conjugates had higher thermal stability than native WPIs and MD. Additionally, cells encapsulated in WPI-EGCG conjugates demonstrated higher in vitro survivability and surface hydrophobicity compared to free or WPI- and MD-encapsulated cells. Furthermore, WPI-EGCG-LA microspheres exerted enhanced in vitro antioxidant (78%) and antidiabetic (52%) activities. Finally, the WPI-EGCG conjugates remarkably improved probiotic viability (8.55 ± 0.1 log cfu/g) during 30 days of storage in an apple juice drink of pH (3.2 ± 0.01). Hence, the WPI-EGCG conjugate represents a propitious carrier to enhance probiotic functional properties upon digestion and during storage in low-pH food products.

Lactobacillus casei LC89 exerts antidiabetic effects through regulating hepatic glucagon response and gut microbiota in type 2 diabetic mice

Previous study suggests that Lactobacillus casei exhibits antihyperglycemic activity, however, the molecular mechanism of this has yet to be elucidated. Here, the anti-diabetic effects and underlying mechanisms of Lactobacillus casei LC89 are investigated in type 2 diabetes mellitus (T2DM) mice, which was induced by a high-fat diet (HFD) with streptozotocin (100 mg per kg BW). The results show that LC89 at a dose of 109 CFU day-1 decreases fasting blood glucose (FBG) and insulin levels by 35.12% and 28.37%, respectively, compared to the diabetes control (DC) group. Moreover, LC89 treatment improved the insulin resistance index (HOMA-IR), serum lipid profiles and inflammation cytokines. The real-time polymerase chain reaction indicated that LC89 markedly downregulates the mRNA expression of hepatic glucagon (GCG), glucagon receptor (GCGR), phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase). Meanwhile, LC89 significantly decreases the abundance of Odoribacter, but increases the Alloprevotella, Bacteroides, Parabacteroides and Ruminococcus content. Therefore, LC89 plays a positive role in alleviating T2DM by regulating gut microbiota and glucagon signal pathway-related genes, and it may be a beneficial dietary supplement to regulate glucose metabolism in T2DM.

The hypoglycemic effect of freeze-dried fermented mulberry mixed with soybean on type 2 diabetes mellitus

Mulberry has significant hypoglycemic effect and can be used as an auxiliary food for people with type 2 diabetes. However, it is rich in carbohydrate and cannot be consumed directly by diabetic patients. In the study, we fermented the mulberry to reduce the content of glucose and fructose, and added the soybean to reduce the loss of probiotics during fermentation and then determined its hypoglycemic effect. We induced type 2 diabetes mellitus (T2DM) mice by streptozotocin and measured its blood glucose, serum biochemistry, hepatic and pancreatic histopathology, and the diversity of the gut microbiota. After 5 weeks of oral DFMS administration, the glucose tolerance was improved significantly in T2DM mice. Furthermore, there were also significant increases in superoxide dismutase activity and glutathione concentration, and marked reductions in the concentrations of malondialdehyde and free fatty acids. Moreover, DFMS also prevented histopathological changes and the increases in the activities of alanine transaminase and aspartate transaminase. DFMS treatment also markedly increased the richness of the gut microbial community. The abundance of Bacteroidetes was increased, and those of Proteobacteria, Escherichia-Shigella, and Lactobacillus were reduced. In summary, DFMS has a clear hypoglycemic effect in mice with T2DM.

Protective Effects of Almond Oil on Streptozotocin-Induced Diabetic Rats via Regulating Nrf2/HO-1 Pathway and Gut Microbiota

Almond oil has been used as a medicine substitution for its numerous health benefits. This study aimed to evaluate the effect of almond oil on streptozotocin- (STZ-) induced diabetic rats for 4 weeks. The results showed that the administration of almond oil could significantly increase body weight, attenuate abnormally elevated blood glucose, promote insulin secretion, and improve glucose tolerance. Almond oil treatment also suppressed oxidative stress, reduced inflammation reaction, improved liver and kidney function, upregulated the expressions of Nrf2, HO-1, and NQO1, while downregulating the expression of Keap1. Furthermore, almond oil reversed the gut microbiota change by STZ and regulated the gut microbiota associated with glucose metabolism. At the phylum level, the relative abundance of Firmicutes was decreased, while Bacteroidetes was increased by almond oil treatment. More importantly, the ratio of Firmicutes/Bacteroidetes was significantly increased. At the genus level, administration of almond oil increased the abundances of Lactobacillus, Bacteroides, and Lachnospiraceae_NK4A136_group, while decreased the abundances of Ruminococcaceae_UCG-014, Clostridium_sensu_stricto_1, and Fusicatenibacter. These results provided evidence for the regulating effect of almond oil on diabetic rats via the Nrf2/HO-1 pathway and gut microbiota.

Protective and ameliorating effects of probiotics against diet-induced obesity: A review

Diet-induced obesity is one of the major public health concerns all over the world, and obesity also contributes to the development of other chronic diseases such as non-alcoholic fatty acid liver disease, type 2 diabetes mellitus and cardiovascular diseases. Evidence shows that the pathogenesis of obesity and obesity-associated chronic diseases are closely related to dysregulation of lipid metabolism, glucose metabolism and cholesterol metabolism, and oxidative stress, endoplasmic reticulum stress, abnormal gut microbiome and chronic low-grade inflammation. Recently, in view of potential effects on lipid metabolism, glucose metabolism, cholesterol metabolism and intestinal microbiome, as well as anti-oxidative and anti-inflammatory activities, natural probiotics, including live and dead probiotics, and probiotic components and metabolites, have attracted increasing attention and are considered as novel strategies for preventing and ameliorating obesity and obesity-related chronic diseases. Specifically, this review is presented on the anti-obesity effects of probiotics and underlying molecular mechanisms, which will provide a theoretical basis of anti-obesity probiotics for the development of functional foods.

Probiotics in the dairy industry-Advances and opportunities

The past two decades have witnessed a global surge in the application of probiotics as functional ingredients in food, animal feed, and pharmaceutical products. Among food industries, the dairy industry is the largest sector where probiotics are employed in a number of dairy products including sour/fermented milk, yogurt, cheese, butter/cream, ice cream, and infant formula. These probiotics are either used as starter culture alone or in combination with traditional starters, or incorporated into dairy products following fermentation, where their presence imparts many functional characteristics to the product (for instance, improved aroma, taste, and textural characteristics), in addition to conferring many health-promoting properties. However, there are still many challenges related to the stability and functionality of probiotics in dairy products. This review highlights the advances, opportunities, and challenges of application of probiotics in dairy industries. Benefits imparted by probiotics to dairy products including their role in physicochemical characteristics and nutritional properties (clinical and functional perspective) are also discussed. We transcend the traditional concept of the application of probiotics in dairy products and discuss paraprobiotics and postbiotics as a newly emerged concept in the field of probiotics in a particular relation to the dairy industry. Some potential applications of paraprobiotics and postbiotics in dairy products as functional ingredients for the development of functional dairy products with health-promoting properties are briefly elucidated.

Orange Juice and Yogurt Carrying Probiotic Bacillus coagulans GBI-30 6086: Impact of Intake on Wistar Male Rats Health Parameters and Gut Bacterial Diversity

This study aimed to investigate the impact of the food matrix (orange juice and yogurt) on the effects of the spore-forming probiotic microorganism Bacillus coagulans GBI-30 6086 in health parameters and gastrointestinal tract (gut) bacterial diversity in Wistar male rats. Rats (n = 48) were randomly distributed into six groups. The groups were the Control (which received sterile distilled water), Juice (which received orange juice), Yogurt (which received yogurt), Probiotic Bacillus (which received B. coagulans GBI-30 6086 in distilled water), Probiotic Juice (which received orange juice with B. coagulans GBI-30 6086), and Probiotic Yogurt (which received yogurt with B. coagulans GBI-30 6086). Each animal belonging to the different groups was treated for 21 days. The daily administration of probiotic juice or probiotic yogurt did not affect the rats’ food or body weight. Rats fed with Probiotic Yogurt showed lower glucose and triglycerides levels (p < 0.05) in comparison to the control group (p < 0.05), while no changes in these parameters were observed in the rats fed with Probiotic Juice. Rats fed with Probiotic Yogurt showed a higher gut bacterial diversity than the control group (p < 0.05), and higher abundance (p < 0.05) of Vibrionales, Enterobacteriales, Burkholderiales, Erysipelotrichales, and Bifidobacteriales compared to all other groups. No changes were observed in the expression levels of antioxidant enzymes or heat shock protein 70 of rats fed with probiotic yogurt or probiotic juice. Results reveal that the consumption of yogurt containing B. coagulans GBI-30 6086 decreases triglycerides and glucose levels and positively impacts the gut bacterial ecology in healthy rats. These animal model findings indicate that the matrix also impacts the functionality of foods carrying spore-forming probiotics. Besides, this research indicates that yogurt is also a suitable food carrier of Bacillus coagulans GBI-30 6086.

Morphological Characteristics of Changes in the Duodenal Wall Within 14-56 Days of the Development of Streptozotocin-Induced Experimental Diabetes Mellitus

The objective of the research was to determine the morphological features of the duodenal wall of animals within 14-56 days of developing streptozotocin-induced diabetes mellitus using light optical microscopy. Materials and Methods. The research was carried out on 40 white nonlinear adult male rats. Diabetes mellitus was simulated by a single intraperitoneal injection of streptozotocin (Sigma, USA) at a dose of 60 mg/kg body weight. The material was taken from the duodenum on the 14th, 28th and the 56th days after the onset of experimental diabetes mellitus. For histological study, the preparations were made using the conventional method, which included the staining of sections with hematoxylin and eosin. Results. Streptozotocin-induced diabetes mellitus was experimentally found to lead to dystrophic changes in the epithelial components of the duodenal mucosa from the 14th day of developing. There were observed a shortening of the villi of the mucous membrane and a lack of distinctness of striated border contours on the apical surface of epitheliocytes. Between the connective-tissue fibers of the lamina propria of the mucosa and thin-walled vessels, the cellular elements, including mainly macrophages, lymphocytes, were found. There was a shortening of the villi, edema and histiolymphocytic infiltration of the villous stroma 28 days after developing experimental diabetes mellitus. The epithelium covering was discontinuous; numerous areas of desquamation were found at the apex of the villi. Fifty-six days after developing experimental diabetes mellitus, the destruction and desquamation of the epithelium of the villi and crypts were observed. The surface of the duodenal mucosa smoothed down due to the shortening and flattening of the villi (indicating their atrophy), while the crypts elongated and their depth increased. Conclusions. Histological study of the duodenal wall of diabetic animals showed pronounced desquamation at the apex of the villi, destructive and dystrophic changes in the surface epithelium, edema and increased cellular infiltration of the lamina propria of the mucosa. Thus, in diabetes mellitus, structural changes in the duodenal wall of rats are characterized by the dystrophic processes, which can be considered as the morphological reflection of enteropathy.

Shorea roxburghii Leaf Extract Ameliorates Hyperglycemia Induced Abnormalities in High Fat/Fructose and Streptozotocin Induced Diabetic Rats

This study investigated the hypoglycemic effect of the methanol extract of Shorea roxburghii leaves (SRL) in high fat diet/high fructose solution (HFDHF) and streptozotocin (STZ) induced type 2 diabetes mellitus (T2DM) in rats as well as evaluating its ameliorative potentials in altered biochemical and hematological parameters in the treated rats. T2DM was induced in Sprague Dawley (SD) rats by feeding with HFDHF for 4 weeks and administering STZ (35 mg/kg, i. p.). Diabetic rats were given SRL extract at doses of 100 and 400 mg/kg for 30 days. The food and water intake were monitored on a daily basis, while the fasting blood glucose (FBG) levels and body weight were measured weekly. Biochemical and hematological parameters as well as histopathological studies of the pancreas were also evaluated. SRL significantly decreased FBG and improved the body weight, food and water intake of treated diabetic rats. Furthermore, biochemical and hematological parameters including liver and kidney function enzymes, lipid profiles, white blood and red blood cells parameters were markedly ameliorated by SRL. Histopathological analyses of the pancreas indicated reconstitution of β-cells architecture in SRL treated rats. The results of this study suggest that SRL has antidiabetic potential and can be considered for the treatment of T2DM.