Asymptomatic chronic gastritis decreases metformin tolerance in patients with type 2 diabetes

Advances in metformin-delivery systems for diabetes and obesity management

Metformin is a medication that is commonly prescribed to manage type 2 diabetes. It has been used for more than 60 years and is highly effective in lowering blood glucose levels. Recent studies indicate that metformin may have additional medical benefits beyond treating diabetes, revealing its potential therapeutic uses. Oral medication is commonly used to administer metformin because of its convenience and cost-effectiveness. However, there are challenges in optimizing its effectiveness. Gastrointestinal side effects and limitations in bioavailability have led to the underutilization of metformin. Innovative drug-delivery systems such as fast-dissolving tablets, micro/nanoparticle formulations, hydrogel and microneedles have been explored to optimize metformin therapy. These strategies enhance metformin dosage, targeting, bioavailability and stability, and provide personalized treatment options for improved glucose homeostasis, antiobesity and metabolic health benefits. Developing new delivery systems for metformin shows potential for improving therapeutic outcomes, broadening its applications beyond diabetes management and addressing unmet medical needs in various clinical settings. However, it is important to improve drug-delivery systems, addressing issues such as complexity, cost, biocompatibility, stability during storage and transportation, loading capacity, required technologies and biomaterials, targeting precision and regulatory approval. Addressing these limitations is crucial for effective, safe and accessible drug delivery in clinical practice. In this review, recent advances in the development and application of metformin-delivery systems for diabetes and obesity are discussed.

Assessment of hepatoprotective, nephroprotective efficacy, and antioxidative potential of Moringa oleifera leaf powder and ethanolic extract against PCOS-induced female albino mice (Mus Musculus)

Moringa oleifera is a medicinal plant that has anti-inflammatory, antihypertensive, antidiabetic, tissue-protective, and antioxidant activities. Here, we evaluated the protective effect of M. oleifera leaf powder (MoLP) and 70% ethanol M. oleifera leaf extract (MoLE) on mitigating polycystic ovary syndrome (PCOS)-induced liver and kidney dysfunction via regulating oxidative stress in female albino mice (Mus musculus). The efficacy of M. oleifera was compared with metformin (standard medicine used to treat infertility in women). PCOS was induced by intramuscular injection of testosterone enanthate at 1.0 mg/100 g BW for 35 days. PCOS-induced mice were treated with MoLP (250 and 500 mg/Kg), MoLE (250 and 500 mg/kg), and metformin (250 mg/kg) orally for 14 days. Renal function test (RFT), liver function test (LFT), and oxidative stress biomarker malondialdehyde (MDA) were quantified in serum at 0, 7, and 14 days of intervention. Mice treated with M. oleifera and metformin showed a significant decrease (p < .001) in alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphate (ALP), total bilirubin, urea, creatinine, and a significant increase (p < .001) in total protein, albumin, globulin, and albumin/globulin (A/G) ratio. Oxidative stress decreased significantly (p = .00) with respect to treatments, exposure days, and their interaction in metformin and all M. oleifera-treated groups. M. oleifera leaf powder and extract reduce oxidative stress and enhance nephron-hepatic activity in PCOS-induced female albino mice.

Gut microbiota is correlated with gastrointestinal adverse events of metformin in patients with type 2 diabetes

Aim

Gastrointestinal discomfort is the most common adverse event in metformin treatment for type 2 diabetes. The mechanism of action of metformin is associated with gut microbiota. However, the gut microbial community structure related to metformin-induced gastrointestinal adverse events remains unclear. This study aimed to investigate it.

Methods

50 patients with newly diagnosed diabetes were treated with metformin 1500mg/d for 12 weeks. The patients were divided into two groups according to whether gastrointestinal adverse events occurred (group B) or did not occur (group A) after treatment. The fecal bacterial communities and short-chain fatty acids (SCFAs) were sequenced and compared. 70 diabetes mice were randomly divided into 8 groups and treated with metformin (Met), clindamycin (Clin) and/or SCFA, which were the Met+/Clin+, Met+/Clin-, Met-/Clin+, Met-/Clin-, Met+/SCFA+, Met+/SCFA-, Met-/SCFA+ and Met-/SCFA- group. After 4 weeks of metformin treatment, blood glucose, food intake, fecal SCFAs, gut microbiota and gut hormones were measured.

Results

Metformin increased the abundance of Phascolarctobacterium, Intestinimonas and Clostridium III. Functional prediction analysis showed that the propanoate metabolism pathway was significantly up-regulated. The concentrations of acetic acid and propanoic acid in feces were significantly increased. The abundance of Clostridium sensu stricto, Streptococcus and Akkermansia induced by metformin in group B was higher than that in group A. The propanoate metabolism pathway and propanoic acid in feces were significantly up-regulated in group B. In the animal experiments, the food intake decreased and glucose control increased in metformin groups compared with those in the control groups. The total GLP-1 level in the Met+/Clin- group was significantly higher than that in the Met-/Clin- group, while there was no statistical difference between the Met-/Clin- and Met+/Clin+ group. The total GLP-1 level in the Met-/SCFA+ group was significantly higher than that in the Met-/SCFA-group, while the levels of total GLP-1 and active GLP-1 in the Met+/SCFA- group and the Met+/SCFA+ group were significantly higher than those in the Met-/SCFA-group.

Conclusions

Our data suggest that metformin promotes the secretion of intestinal hormones such as GLP-1 by increasing the abundance of SCFA-producing bacteria, which not only plays an anti-diabetic role, but also may causes gastrointestinal adverse events.

Effectiveness of Moringa oleifera Leaves on TNF-α Expression, Insulin Levels, Glucose Levels and Follicle Count in Rattus norvegicus PCOS Model

BACKGROUND

Polycystic ovary syndrome (PCOS) is a syndrome characterized by ovulation disorders accompanied by hyperandrogens. Women with PCOS are prone to develop insulin resistance which has metabolic characteristics similar to type 2 diabetes and leads to disturbance of follicular formation. PCOS is also known to increase the concentration of proinflammatory cytokines, namely TNF-α. Moringa oleifera leaves have been shown to have compounds that can reduce insulin levels and glucose levels in diabetes mellitus and should be able to reduce TNF-α and follicle count.

PURPOSE

This study aims to prove the effectiveness of Moringa oleifera leaf in reducing insulin, glucose levels, TNF-α and follicle count in PCOS.

METHODS

The three-month-old white rats Wistar (Rattus norvegicus) 150-170 grams were divided into four groups (n = 10), namely normal rats, PCOS model rats, PCOS model rats given metformin, and PCOS rats given 500mg of Moringa oleifera. The method of this study is taking PCOS model rats by injecting the 100mg/kg BW hormone testosterone propionate for 21 days. After 21 days of therapy, we analyzed insulin, glucose levels, TNF-α and follicle count.

RESULTS

The PCOS control group showed an increase in insulin level, glucose levels, TNF-α expression, and a decrease in the follicle count compared to the normal control group. The insulin level, glucose level, TNF-α and follicle count in the Moringa oleifera 500 mg/kg BW treatment group were significantly lower than in the PCOS control group.

CONCLUSION

Moringa oleifera leaves have the potential in reducing insulin levels, blood glucose levels, TNF-α and follicle count in PCOS patients.

The effect of genistein on insulin resistance, inflammatory factors, lipid profile, and histopathologic indices in rats with polycystic ovary syndrome

OBJECTIVE

Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, irregular menstruation, ovulatory dysfunction, and insulin resistance. Recent studies have reported the possible role of phytoestrogens in PCOS. This animal study aimed to evaluate the effects of genistein on insulin resistance, inflammatory factors, lipid profile, and histopathologic indices on PCOS.

METHODS

PCOS was induced by 1 mg/kg of letrozole in adult Sprague-Dawley rats. The rats then received normal saline (PCOS group), 150 mg/kg of metformin, or 20 mg/kg of genistein dissolved in 1% methylcellulose solution for 42 days. Body weight, the glycemic and lipid profile, and inflammatory, antioxidative, and histopathological parameters were assessed at the end of the intervention.

RESULTS

Treatment with genistein significantly alleviated the increased level of fasting blood insulin (p=0.16) and the homeostatic model assessment of insulin resistance (p=0.012). In addition, the genistein group had significantly lower levels of serum malondialdehyde (p=0.039) and tumor necrosis factor-alpha (p=0.003), and higher superoxide dismutase enzyme activity (p<0.001). Furthermore, the histopathological analysis indicated that genistein administration led to an increase in luteinization and the development of fewer cysts (p<0.05).

CONCLUSION

Biochemical and histopathological analyses indicated that genistein administration to rats with PCOS induced significant remission in oxidative, inflammatory, and glycemic and histopathologic parameters.

Pachymic acid protects oocyte by improving the ovarian microenvironment in polycystic ovary syndrome mice†

Women with polycystic ovary syndrome (PCOS) are characterized by endocrine disorders accompanied by a decline in oocyte quality. In this study, we generated a PCOS mice model by hypodermic injection of dehydroepiandrosterone, and metformin was used as a positive control drug to study the effect of pachymic acid (PA) on endocrine and oocyte quality in PCOS mice. Compared with the model group, the mice treated with PA showed the following changes (slower weight gain, improved abnormal metabolism; increased development potential of GV oocytes, reduced number of abnormal MII oocytes, and damaged embryos; lower expression of ovarian-related genes in ovarian tissue and pro-inflammatory cytokines in adipose tissue). All these aspects show similar effects on metformin. Most notably, PA is superior to metformin in improving inflammation of adipose tissue and mitochondrial abnormalities. It is suggested that PA has the similar effect with metformin, which can improve the endocrine environment and oocyte quality of PCOS mice. These findings suggest that PA has the similar effect with metformin, which can improve the endocrine environment and oocyte quality of PCOS mice.

Cryptotanshinone alleviates polycystic ovary syndrome in rats by regulating the HMGB1/TLR4/NF‑κB signaling pathway

Cryptotanshinone (CRY) has been demonstrated to reverse reproductive disorders. However, whether CRY is effective in the treatment of polycystic ovary syndrome (PCOS) remains unknown. The aim of the present study was to evaluate the therapeutic potential of CRY in PCOS. A rat model of PCOS was established by daily injection of human chorionic gonadotropin and insulin for 22 days. Total body weight and ovarian weight, as well as the levels of luteinizing hormone (LH) and the LH to follicle-stimulating hormone (FSH) ratio (LH/FSH) significantly increased in rats with PCOS, compared with controls. Moreover, the levels of testosterone (T), tumor necrosis factor (TNF)-α and high-mobility group box 1 protein (HMGB1) also increased. However, CRY treatment attenuated the increase in body weight, ovarian weight, LH, LH/FSH ratio, T, TNF-α and HMGB1 levels, compared with the PCOS group. Treatment with CRY also reduced NF-κB/p65, HMGB1 and toll-like receptor (TLR)4 mRNA and protein expression levels in the ovarian tissue and granulosa cells, both in vitro and in vivo. Thus, CRY significantly mitigated the changes in body weight, ovary weight, hormone levels and inflammatory factor levels observed in rats with PCOS. Thus, CRY protects against PCOS-induced damage of ovarian tissue, possibly through a regulatory pathway involving HMGB1, TLR4 and NF-κB.

Comparison of gastrointestinal adverse events with different doses of metformin in the treatment of elderly people with type 2 diabetes

WHAT IS KNOWN AND OBJECTIVE

Gastrointestinal discomfort is the most common adverse event of metformin treatment for type 2 diabetes, especially in elderly patients. The aim of this study was to compare gastrointestinal adverse events resulting from different doses of metformin used for the treatment of elderly people with type 2 diabetes.

METHODS

A total of 361 elderly patients with newly diagnosed diabetes were randomly divided into three groups: metformin 1000 mg/d (N = 120), metformin 1500 mg/d (N = 121) and metformin 2000 mg/d (N = 120). Glycaemic control and gastrointestinal adverse events (abdominal pain, diarrhoea, nausea, vomiting, bloating and anorexia) were assessed and compared among the three groups after 12 weeks of treatment.

RESULTS AND DISCUSSION

At baseline, there was no significant difference in gastrointestinal symptoms among the three groups. After 12 weeks of treatment with metformin, the change in HbA_1c level was -0.7%, -0.9% and -1.0% for the 1000 mg/d, 1500 mg/d and 2000 mg/d groups, respectively (P < .0001). There was no significant difference in gastrointestinal adverse events among the three groups after treatment with metformin. In total, 62 people (17.2%) could not tolerate the adverse effects of metformin, and most of them stopped treatment in the first 4 weeks. Logistic regression analysis shows that female sex (OR = 2.660, 95%CI 1.692-4.183, P < .0001) and the concurrent use of organic cation transporter 1-inhibiting drugs (OR = 1.874, 95%CI 1.076-3.265, P = .027) are independent risk factors for adverse events.

WHAT IS NEW AND CONCLUSIONS

Our data demonstrate that metformin doses of 1000 mg/d-2000 mg/d have similar adverse events but that 2000 mg/d of metformin yields the best glycaemic control in elderly people with diabetes. If elderly people can tolerate 1000 mg/d of metformin, we could gradually increase the dose to 2000 mg/d to achieve better glycaemic control.

Effects of Moringa oleifera on Insulin Levels and Folliculogenesis in Polycystic Ovary Syndrome Model with Insulin Resistance

Background:

Insulin resistance is a frequent metabolic disorder in Polycystic Ovary Syndrome (PCOS). Moringa oleifera has been shown to increase insulin expres-sion and decrease the degree of insulin in diabetes mellitus, therefore it is expected that Moringa oleifera could decrease insulin levels and increase folliculogenesis in PCOS.

Objective:

To prove the effect of Moringa oleifera leaf extract in various doses might decrease the insulin levels and increase folliculogenesis in female PCOS-insulin resistant rats.

Methods:

The three month old white rat of Wistar strain (Rattus norvegicus) 100-130 grams were divided into five groups (n=8) including normal control, PCOS-insulin re-sistance, PCOS-insulin resistance given metformin and PCOS-resistance insulin were giv-en Moringa oleifera leaf extract in two doses. Then, the PCOS model-insulin resistance by injection of testosterone propionate for 28 days. After 14 days treatment, we analysed insulin levels and folliculogenesis.

Results:

The PCOS control group showed a significant increase in insulin levels compared to the normal control group. The insulin levels from group treatment with Moringa oleifera leaf extract of 250 mg/kgBW was significantly lower than the PCOS control group. Ovarian histology analysis found that the number and diameter of follicle of PCOS control group showed a significant decrease compared to normal control group. In addition, the treatment with metformin and leaf Moringa oleifera dose 250 mg/kgBW and 500 mg/kgBW showed significant increase of folliculogenesis compared to PCOS control group.

Conclusions:

Moringa oleifera could lowering the blood insulin levels, subsequently decreasing the androgen thus allowed the increasing of folliculogenesis in PCOS.

Understanding and overcoming metformin gastrointestinal intolerance

Metformin is the most widely prescribed drug for patients with type 2 diabetes mellitus and the first-line pharmacological option as supported by multiple international guidelines, yet a rather large proportion of patients cannot tolerate metformin in adequate amounts because of its associated gastrointestinal (GI) adverse events (AEs). GI AEs typically encountered with metformin therapy include diarrhoea, nausea, flatulence, indigestion, vomiting and abdominal discomfort, with diarrhoea and nausea being the most common. Although starting at a low dose and titrating slowly may help prevent some GI AEs associated with metformin, some patients are unable to tolerate metformin at all and it may also be difficult to convince patients to start metformin again after a bout of GI AEs. Despite this clinical importance, the underlying mechanisms of the GI intolerance associated with metformin are poorly known. In the present review, we discuss: the epidemiology of metformin-associated GI intolerance and its underlying mechanisms; genotype variability and associated factors affecting metformin GI intolerance, such as comorbidities, co-medications and bariatric surgery; clinical consequences and therapeutic strategies to overcome metformin GI intolerance. These strategies include appropriate titration of immediate-release metformin, use of extended-release metformin, the promise of delayed-release metformin and gut microbiome modulators, as well as alternative pharmacological therapies when metformin cannot be tolerated at all. Given the available data, all efforts should be made to maintain metformin before considering a shift to another drug therapy.