Type 2 Diabetes Variants Disrupt Function of SLC16A11 through Two Distinct Mechanisms.

Type 2 diabetes (T2D) affects Latinos at twice the rate seen in populations of European descent. We recently identified a risk haplotype spanning SLC16A11 that explains ∼20% of the increased T2D prevalence in Mexico. Here, through genetic fine-mapping, we define a set of tightly linked variants likely to contain the causal allele(s). We show that variants on the T2D-associated haplotype have two distinct effects: (1) decreasing SLC16A11 expression in liver and (2) disrupting a key interaction with basigin, thereby reducing cell-surface localization. Both independent mechanisms reduce SLC16A11 function and suggest SLC16A11 is the causal gene at this locus. To gain insight into how SLC16A11 disruption impacts T2D risk, we demonstrate that SLC16A11 is a proton-coupled monocarboxylate transporter and that genetic perturbation of SLC16A11 induces changes in fatty acid and lipid metabolism that are associated with increased T2D risk. Our findings suggest that increasing SLC16A11 function could be therapeutically beneficial for T2D. VIDEO ABSTRACT.

Multiple genetic variants at the SLC30A8 locus affect local super-enhancer activity and influence pancreatic ß-cell survival and function.

Variants at the SLC30A8 locus are associated with type 2 diabetes (T2D) risk. The lead variant, rs13266634, encodes an amino acid change, Arg325Trp (R325W), at the C-terminus of the secretory granule-enriched zinc transporter, ZnT8. Although this protein-coding variant was previously thought to be the sole driver of T2D risk at this locus, recent studies have provided evidence for lowered expression of SLC30A8 mRNA in protective allele carriers. In the present study, we examined multiple variants that influence SLC30A8 allele-specific expression. Epigenomic mapping has previously identified an islet-selective enhancer cluster at the SLC30A8 locus, hosting multiple T2D risk and cASE associations, which is spatially associated with the SLC30A8 promoter and additional neighboring genes. Here, we show that deletion of variant-bearing enhancer regions using CRISPR-Cas9 in human-derived EndoC-ßH3 cells lowers the expression of SLC30A8 and several neighboring genes and improves glucose-stimulated insulin secretion. While downregulation of SLC30A8 had no effect on beta cell survival, loss of UTP23, RAD21, or MED30 markedly reduced cell viability. Although eQTL or cASE analyses in human islets did not support the association between these additional genes and diabetes risk, the transcriptional regulator JQ1 lowered the expression of multiple genes at the SLC30A8 locus and enhanced stimulated insulin secretion.

A distinct role of STING in regulating glucose homeostasis through insulin sensitivity and insulin secretion.

Insulin resistance and ß-cell dysfunction are two main molecular bases yet to be further elucidated for type 2 diabetes (T2D). Accumulating evidence indicates that stimulator of interferon genes (STING) plays an important role in regulating insulin sensitivity. However, its function in ß-cells remains unknown. Herein, using global STING knockout (STING-/-) and ß-cell-specific STING knockout (STING-ßKO) mouse models, we revealed a distinct role of STING in the regulation of glucose homeostasis through peripheral tissues and ß-cells. Specially, although STING-/- beneficially alleviated insulin resistance and glucose intolerance induced by high-fat diet, it surprisingly impaired islet glucose-stimulated insulin secretion (GSIS). Importantly, STING is decreased in islets of db/db mice and patients with T2D, suggesting a possible role of STING in ß-cell dysfunction. Indeed, STING-ßKO caused glucose intolerance due to impaired GSIS, indicating that STING is required for normal ß-cell function. Islet transcriptome analysis showed that STING deficiency decreased expression of ß-cell function-related genes, including Glut2, Kcnj11, and Abcc8, contributing to impaired GSIS. Mechanistically, the assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) and cleavage under targets and tagmentation (CUT&Tag) analyses suggested that Pax6 was the transcription factor that might be associated with defective GSIS in STING-ßKO mice. Indeed, Pax6 messenger RNA and protein levels were down-regulated and its nuclear localization was lost in STING-ßKO ß-cells. Together, these data revealed a function of STING in the regulation of insulin secretion and established pathophysiological significance of fine-tuned STING within ß-cells and insulin target tissues for maintaining glucose homeostasis.

The Global Epidemiology of Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis Among Patients With Type 2 Diabetes.

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD), now known as metabolic dysfunction associated steatotic liver disease (MASLD), is closely associated with type 2 diabetes (T2D). Our aim was to estimate the most recent global prevalence of NAFLD/MASLD, nonalcoholic steatohepatitis (NASH), now known as metabolic dysfunction associated steatohepatitis (MASH), advanced fibrosis, and mortality among patients with T2D. METHODS: We systematically searched PubMed and Ovid MEDLINE for terms including NAFLD, NASH, and T2D published in 1990-2023 according to PRISMA. The meta-analysis was conducted using a random-effects model. Assessment of bias risk used the Joanna Briggs Institute appraisal tool. RESULTS: From 3134 studies included in the initial search, 123 studies (N = 2,224,144 patients with T2D) were eligible. Another 12 studies (N = 2733 T2D patients with liver biopsy) were eligible for histologic assessments. The global pooled prevalence of NAFLD/MASLD among patients with T2D was 65.33% (95% confidence interval, 62.35%-68.18%). This prevalence increased from 55.86% (42.38%-68.53%) in 1990-2004 to 68.81% (63.41%-73.74%) in 2016-2021 (P = .073). The highest NAFLD/MASLD prevalence among T2D patients was observed in Eastern Europe (80.62%, 75.72%-84.73%), followed by the Middle East (71.24%, 62.22%-78.84%), and was lowest in Africa (53.10%, 26.05%-78.44%). Among patients with liver biopsy data, the global pooled prevalence of NASH/MASH, significant fibrosis, and advanced fibrosis was 66.44% (56.61%-75.02%), 40.78% (24.24%-59.70%), and 15.49% (6.99%-30.99%), respectively. The pooled all-cause mortality was 16.79 per 1000 person-years (PY) (10.64-26.40), 4.19 per 1000 PY (1.34-7.05) for cardiac-specific mortality; 6.10 per 1000 PY (0.78-4.88) for extrahepatic cancer-specific mortality; and 2.15 per 1000 PY (0.00-2.21) for liver-specific mortality. CONCLUSIONS: The prevalence of NAFLD/MASLD among T2D is high and growing. The majority of NAFLD/MASLD patients with T2D have NASH/MASH, and a significant proportion have advanced fibrosis.

Association study between adiponectin gene variants, serum levels and the risk of type 2 diabetes in Tunisian women: Insights from BMI stratification.

Although prior studies have shown that adiponectin synthesis is genetically determined and that its levels influence susceptibility to T2D, the results in this regard have been inconsistent. This study aims, to investigate the relationship between adiponectin gene variants with the risk of developing T2D among Tunisian women and in relation to their BMI status. A cohort of 491 Tunisian T2D women and 373 non-diabetic subjects participated in the study. Nine ADIPOQ variants namely rs16861194, rs17300539, rs266729, rs822395, rs822396, rs2241766, rs1501299, rs2241767 and rs3774261 were selected and genotyped using the TaqMan® SNP genotyping assay. Fasting serum adiponectin levels were quantified using ELISA. The results showed that only the rs17300539 variant exhibited a significant association with the risk of T2D. However, upon considering T2D group stratification based on BMI (normal weight [18-24.99 Kg/m2], overweight [25-29.99 Kg/m2] and obese [30-34.99 Kg/m2]), the ADIPOQ rs2241766 variant emerged as a contributing risk factor for increased BMI in obese women with T2D. Linear regression analysis revealed that the minor allele (A), (GA) and (AA) genotypes of rs17300539 as well as the (G) allele and (GG) genotype of rs2241766 were significantly associated with hypoadiponectinemia in T2D subjects. Two haplotypes namely GGCAATGAA and AGCCGTGGA, were identified as conferring a higher risk of T2D with the GGCAATGAA haplotype also correlating with hypoadiponectinemia. Our study underscores the importance of the rs17300539 variant and the GGCAATGAA haplotype in the risk of T2D and hypoadiponectinemia. Additionally, the presence of the rs2241766 variant highlights its association with 'diabesity' and hypoadiponectinemia among Tunisian T2D women.

Influence of sphingolipid enzymes on blood glucose levels, development of diabetes, and involvement of pericytes.

AIMS: Sulfatide is a chaperone for insulin manufacturing in beta cells. Here we explore whether the blood glucose values normally could be associated with this sphingolipid and especially two of its building enzymes CERS2 and CERS6. Both T1D and T2D have low blood sulfatide levels, and insulin resistance on beta cells at clinical diagnosis. Furthermore, we examined islet pericytes for sulfatide, and beta-cell receptors for GLP-1, both of which are related to the insulin production. MATERIALS AND METHODS: We examined mRNA levels in islets from the DiViD and nPOD studies, performed genetic association analyses, and histologically investigated pericytes in the islets for sulfatide. RESULTS: Polymorphisms of the gene encoding the CERS6 enzyme responsible for synthesising dihydroceramide, a precursor to sulfatide, are associated with random blood glucose values in non-diabetic persons. This fits well with our finding of sulfatide in pericytes in the islets, which regulates the capillary blood flow in the islets of Langerhans, which is important for oxygen supply to insulin production. In the islets of newly diagnosed T1D patients, we observed low levels of GLP-1 receptors; this may explain the insulin resistance in their beta cells and their low insulin production. In T2D patients, we identified associated polymorphisms in both CERS2 and CERS6. CONCLUSIONS: Here, we describe several polymorphisms in sulfatide enzymes related to blood glucose levels and HbA1c in non-diabetic individuals. Islet pericytes from such persons contain sulfatide. Furthermore, low insulin secretion in newly diagnosed T1D may be explained by beta-cell insulin resistance due to low levels of GLP-1 receptors.

TorS - Reframing a rational for type 2 diabetes treatment.

The mammalian target of rapamycin complex 1 syndrome (Tors), paradigm implies an exhaustive cohesive disease entity driven by a hyperactive mTORC1, and which includes obesity, type 2 diabetic hyperglycemia, diabetic dyslipidemia, diabetic cardiomyopathy, diabetic nephropathy, diabetic peripheral neuropathy, hypertension, atherosclerotic cardiovascular disease, non-alcoholic fatty liver disease, some cancers, neurodegeneration, polycystic ovary syndrome, psoriasis and other. The TorS paradigm may account for the efficacy of standard-of-care treatments of type 2 diabetes (T2D) in alleviating the glycaemic and non-glycaemic diseases of TorS in T2D and non-T2D patients. The TorS paradigm may generate novel treatments for TorS diseases.

Weight-related discrimination, perceived stress and psychological and physical well-being of persons with type 2 diabetes: A mediation analysis.

AIMS: The aim of the study was to examine perceived stress as a mediator of the association between weight-related discrimination and physical and psychological well-being among persons with type 2 diabetes (T2D). METHODS: Data were obtained from 5104 persons with self-reported T2D participating in the All of Us research programme in the United States. The Everyday Discrimination Scale, Cohen's Perceived Stress Scale (PSS) and PROMIS Global Health Scale were used to measure weight-related discrimination, perceived stress and health outcomes (physical and psychological), respectively. Mediation effects of PSS were tested by bootstrapping with 5000 random samples. RESULTS: Participants were, on average, 63.62 (SD 11.38) years old. Majority of them were female (55.53%), non-Hispanic White (72.61%), married or living with a partner (56.92%), had a household income of <$35,000 (31.99%) and had some college education (33.54%). We found that approximately 18% of study participants reported having experienced weight-related discrimination. We also found that weight-related discrimination was independently associated with poor physical and psychological well-being. These associations were partially mediated by perceived stress such that weight-related discrimination was associated with greater perceived stress, which was in turn associated with poorer physical and psychological well-being. CONCLUSIONS: Given that weight-related discrimination is associated with poor outcomes through elevated stress, interventions that target stress may disrupt this pathway thereby helping to reduce the health impact of weight-related discrimination. This assertion should, however, be tested in future studies.

Insulin sensitivity and beta cell function after Duodenal Mucosal Resurfacing (DMR): An Open-Label, Mechanistic, Pilot Study.

BACKGROUND AND AIMS: The duodenum has been shown to play a key role in glucose homeostasis. Duodenal mucosal resurfacing (DMR) is an endoscopic procedure for patients with type 2 diabetes (T2D) in which the duodenal mucosa is hydrothermally ablated. DMR improves glycemic control, but the underlying mechanisms remain unclear. Here, we report changes in glucoregulatory hormones and indices of insulin sensitivity and beta cell function after DMR. METHODS: We included 28 patients on non-insulin glucose lowering medications who underwent open-label DMR and a mixed meal test (MMT) in Revita-1 or Revita-2. Inclusion criteria were hemoglobin A1c (HbA1c) 7.6-10.4% and BMI 24-40kg/m2. Baseline and 3-months MMT data included plasma glucose, insulin, C-peptide, glucagon-like peptide-1 (GLP-1), and gastric inhibitory polypeptide (GIP) concentrations. Glucoregulatory hormones, insulin sensitivity indices (homeostatic model assessment for insulin resistance [HOMA-IR], Matsuda index [MI] and hepatic insulin resistance [HIR]), and beta cell function (insulinogenic index [IGI], disposition index [DI] and insulin secretion rate [ISR]) were assessed. RESULTS: Fasting insulin, glucagon, and C-peptide decreased significantly. Insulin sensitivity (HOMA-IR, MI, and HIR) and beta cell function (DI and ISR) all improved significantly. Decline in postprandial glucose, mainly driven by a decrease in fasting levels, was observed, as well as a decline in postprandial glucagon whereas GLP-1 and GIP did not change. CONCLUSIONS: Insulin sensitivity and insulin secretion improved 3 months after DMR. It is unlikely that incretin changes are responsible for improved glucose control after DMR. These data add to the growing evidence validating the duodenum as a therapeutic target for patients with T2D.

Prevalence of metabolic dysfunction-associated steatotic liver disease in the Middle East and North Africa.

BACKGROUND AND AIMS: Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease (NAFLD), is common and closely associated with type 2 diabetes (T2D). We assessed the prevalence of NAFLD/MASLD in the general population and among patients with T2D in the Middle East and North Africa (MENA) region. METHODS: We searched PubMed and Embase for English-language articles published between 1990 and 2023 according to PRISMA. Each country's NAFLD/MASLD prevalence in the general population and in T2D patients was predicted by using a multivariable meta regression model. Input data were extracted from our systematic review, GBD and NCD Risk Factor Collaboration. Confidence intervals were constructed by using prediction intervals with the delta method. RESULTS: Meta-analytic pooling estimated the prevalence of NAFLD/MASLD as 39.43% in the general population and 68.71% among T2D patients. NAFLD/MASLD prevalence has increased from 35.42% (2008-2016) to 46.20% (2017-2020). Using GBD-2019 dataset, it was predicted that there are 141.51 million cases of NAFLD/MASLD in the MENA region. The highest number of NAFLD/MASLD cases were expected in Egypt (25.71 million), followed by Türkiye (23.33 million) and Iran (19.85 million). Estimated NAFLD prevalence exceeded 40% in 10 of 21 countries with the top countries being Kuwait (45.37%), Egypt (45.0%), Qatar (44.4%), and Jordan (43.3%). Furthermore, it was predicted that there are 24.96 million cases of NAFLD/MASLD with T2D in the MENA region. CONCLUSIONS: In the MENA region, prevalence of NAFLD/MASLD is very high and growing, necessitating an urgent need for regional public policy to deal with this growing burden.

Type 2 diabetes mellitus pharmacological remission with dapagliflozin plus oral semaglutide.

Dapagliflozin, a sodium-glucose co-transporter-2 inhibitor and semaglutide, a glucagon-like peptide 1 receptor agonist, have both demonstrated efficacy in glycemic control, reducing blood pressure, body weight, risk of renal and heart failure in type 2 diabetes mellitus. In this observational, real-world, study we aimed to investigate the efficacy of the combination therapy with those two agents over glycemic control. We thus obtained the data of 1335 patients with type 2 diabetes followed by 11 Diabetes centers in Lombardia, Italy. A group of 443 patients was treated with dapagliflozin alone, the other group of 892 patients was treated with the combination therapy of dapagliflozin plus oral semaglutide. We analyzed changes in glycated hemoglobin from baseline to 6 months of follow-up, as well as changes in fasting glycemia, body weight, body mass index, systolic and diastolic pressure, heart rate, creatinine, estimated glomerular filtration rate and albuminuria. Both groups of patients showed an improvement of glycometabolic control after 6 months of treatment; indeed, the treatment with dapagliflozin plus oral semaglutide showed a reduction of glycated hemoglobin of 1.2% as compared to the 0.5% reduction observed in the dapagliflozin alone group. Significant changes were observed in body mass index, fasting plasmatic glucose, blood pressure, total cholesterol, LDL and albumin to creatinine ratio, with a high rate (55%) of near-normalization of glycated hemoglobin. Our real world data confirmed the potential of the oral combination therapy dapagliflozin with semaglutide in inducing pharmacological remission of type 2 diabetes mellitus.

Assessing the importance of primary care diagnoses in the UK Biobank.

The UK Biobank has made general practitioner (GP) data (censoring date 2016-2017) available for approximately 45% of the cohort, whilst hospital inpatient and death registry (referred to as "HES/Death") data are available cohort-wide through 2018-2022 depending on whether the data comes from England, Wales or Scotland. We assessed the importance of case ascertainment via different data sources in UKB for three diseases that are usually first diagnosed in primary care: Parkinson's disease (PD), type 2 diabetes (T2D), and all-cause dementia. Including GP data at least doubled the number of incident cases in the subset of the cohort with primary care data (e.g. from 619 to 1390 for dementia). Among the 786 dementia cases that were only captured in the GP data before the GP censoring date, only 421 (54%) were subsequently recorded in HES. Therefore, estimates of the absolute incidence or risk-stratified incidence are misleadingly low when based only on the HES/Death data. For incident cases present in both HES/Death and GP data during the full follow-up period (i.e. until the HES censoring date), the median time difference between an incident diagnosis of dementia being recorded in GP and HES/Death was 2.25 years (i.e. recorded 2.25 years earlier in the GP records). Similar lag periods were also observed for PD (median 2.31 years earlier) and T2D (median 2.82 years earlier). For participants with an incident GP diagnosis, only 65.6% of dementia cases, 69.0% of PD cases, and 58.5% of T2D cases had their diagnosis recorded in HES/Death within 7 years since GP diagnosis. The effect estimates (hazard ratios, HR) of established risk factors for the three health outcomes mostly remain in the same direction and with a similar strength of association when cases are ascertained either using HES only or further adding GP data. The confidence intervals of the HR became narrower when adding GP data, due to the increased statistical power from the additional cases. In conclusion, it is desirable to extend both the coverage and follow-up period of GP data to allow researchers to maximise case ascertainment of chronic health conditions in the UK.

Nutrient patterns and risk of diabetes mellitus type 2: a case-control study.

BACKGROUNDS: Although the significance of diet in preventing or managing diabetes complications is highlighted in current literature, there is insufficient evidence regarding the correlation between nutrient patterns and these complications. The objective of this case-control study is to investigate this relationship by analyzing the dietary intake of nutrients in participants with and without type 2 diabetes (T2D). METHODS: A case-control study was conducted at the Tabriz Center of Metabolism and Endocrinology to investigate the relationship between nutrient patterns and type 2 diabetes (T2D). The study enrolled 225 newly diagnosed cases of T2D and 225 controls. The dietary intake of nutrients was assessed using a validated semi-quantitative food frequency questionnaire (FFQ). Principal component analysis using Varimax rotation was used to obtain nutrient patterns. Logistic regression analysis was performed to estimate the risk of T2D. RESULTS: The participants' mean (SD) age and BMI were 39.8 (8.8) years and 27.8 (3.6) kg/m2, respectively. The results identified three major nutrient patterns. The first nutrient pattern was characterized by high consumption of sucrose, animal protein, vitamin E, vitamin B1, vitamin B12, calcium, phosphorus, zinc, and potassium. The second nutrient pattern included fiber, plant protein, vitamin D, Riboflavin, Vitamin B5, copper, and Magnesium. The third nutrient pattern was characterized by fiber, plant protein, vitamin A, riboflavin, vitamin C, calcium, and potassium. Individuals in the highest tertile of nutrient pattern 3 (NP3) had a lower risk of T2D compared to those in the lowest tertile after adjusting for confounders. The odds ratio was 0.52 with a 95% confidence interval of 0.30-0.89 and a P_trend of 0.039. CONCLUSION: This study found that conforming to a nutrient pattern consisting of plant protein, vitamin C, vitamin A, vitamin B2, potassium, and calcium is linked to a lower likelihood of developing T2D.The initial results suggest that following a nutrient pattern that includes these nutrients may reduce the risk of T2D. However, further research is required to confirm the relationship between nutrient patterns and T2D.

Serum selenium and fasting blood glucose: a cross-sectional study in women of different menopause status.

BACKGROUND: This cross-sectional study aims to explore whether there exists an interaction between selenium and menopause concerning type 2 diabetes (T2D) prevalence and its related indicators such as fasting blood glucose (FBG) and homeostasis model assessment of insulin resistance (HOMA-IR). METHODS: 150 women aged 35-60 years old were finally analyzed in this study. Multivariate linear or logistic regression modeling was conducted to explore the association of selenium and the prevalence of T2D besides its related indicators. Subgroup analyses were conducted based on menopause status to assess the potential impact on the relationship. RESULTS: In the fully adjusted model, serum selenium was positively associated with FBG (ß: 0.03, CI: 0.01-0.05) and the prevalence of T2D (OR: 1.04, CI: 1.00-1.08). After stratifying the data by menopause status, compared with the postmenopausal women group, as the serum selenium concentrations increased, the FBG concentrations were significantly higher in the premenopausal women group (p for interaction = 0.0020). CONCLUSIONS: The present study found serum selenium was positively associated with FBG and the prevalence of T2D. Furthermore, the relationship between serum selenium and FBG was different in the premenopausal and postmenopausal women. More studies are still needed in the future to verify the relationship as well as to explore the specific mechanisms.

Air pollution, life's essential 8, and risk of severe non-alcoholic fatty liver disease among individuals with type 2 diabetes.

BACKGROUND: The impacts of long-term exposure to air pollution on the risk of subsequent non-alcoholic fatty liver disease (NAFLD) among participants with type 2 diabetes (T2D) is ambiguous. The modifying role of Life's Essential 8 (LE8) remains unknown. METHODS: This study included 23,129 participants with T2D at baseline from the UK Biobank. Annual means of nitrogen dioxide (NO2), nitrogen oxides (NOX), and particulate matter (PM2.5, PM2.5-10, PM10) were estimated using the land-use regression model for each participant. The associations between exposure to air pollution and the risk of severe NAFLD were evaluated using Cox proportional hazard models. The effect modification of LE8 was assessed through stratified analyses. RESULTS: During a median 13.6 years of follow-up, a total of 1,123 severe NAFLD cases occurred. After fully adjusting for potential covariates, higher levels of PM2.5 (hazard ratio [HR] = 1.12, 95%CI:1.02, 1.23 per interquartile range [IQR] increment), NO2 (HR = 1.15, 95%CI:1.04, 1.27), and NOX (HR = 1.08, 95%CI:1.01, 1.17) were associated with an elevated risk of severe NAFLD. In addition, LE8 score was negatively associated with the risk of NAFLD (HR = 0.97, 95% CI: 0.97, 0.98 per point increment). Compared with those who had low air pollution and high LE8, participants with a high air pollution exposure and low LE8 had a significantly higher risk of severe NAFLD. CONCLUSIONS: Our findings suggest that long-term exposure to air pollution was associated with an elevated risk of severe NAFLD among participants with T2D. A lower LE8 may increase the adverse impacts of air pollution on NAFLD.

Investigations of Limeum Indicum Plant for Diabetes Mellitus and Alzheimer's Disease Dual Therapy: Phytochemical, GC-MS Chemical Profiling, Enzyme Inhibition, Molecular Docking and In-Vivo Studies.

Limeum indicum has been widely utilized in traditional medicine but no experimental work has been done on this herb. The primary objective of this study was to conduct a phytochemical analysis and assess the multifunctional capabilities of aforementioned plant in dual therapy for Alzheimer's disease (AD) and Type 2 diabetes (T2D). The phytochemical screening of ethanol, methanol extract, and their derived fractions of Limeum indicum was conducted using GC-MS, HPLC, UV-analysis and FTIR. The antioxidant capacity was evaluated by DPPH method. The inhibitory potential of the extracts/fractions against α-, ß-glucosidase acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and monoaminine oxidases (MAO-A & B) was evaluated. Results revealed that acetonitrile fraction has highest inhibitory potential against α-glucosidase (IC50=68.47±0.05 µg/mL), methanol extract against ß-glucosidase (IC50=91.12±0.07 µg/mL), ethyl acetate fraction against AChE (IC50=59.0±0.02 µg/mL), ethanol extract against BChE (28.41±0.01 µg/mL), n-hexane fraction against MAO-A (IC50=150.5±0.31 µg/mL) and methanol extract for MAO-B (IC50=75.95±0.13 µg/mL). The docking analysis of extracts\fractions suggested the best binding scores within the active pocket of the respective enzymes. During the in-vivo investigation, ethanol extract produced hypoglycemic effect (134.52±2.79 and 119.38±1.40 mg/dl) after 21 days treatment at dose level of 250 and 500 mg/Kg. Histopathological findings further supported the in-vivo studies.

Okinawa-Based Nordic Diet Decreases Plasma Levels of IAPP and IgA against IAPP Oligomers in Type 2 Diabetes Patients.

Pancreas-derived islet amyloid polypeptide (IAPP) aggregates and deposits in the pancreas and periphery of Type 2 Diabetes (T2D) patients, contributing to diabetic complications. The excess IAPP can be removed by autoantibodies, and increased levels of immunoglobulin (Ig) G against IAPP have been reported in T2D patients. However, whether other Ig classes are also affected and if the levels can be managed is less known. This pre-post study examines IgA levels against IAPP oligomers (IAPPO-IgA) in T2D patients and assesses the impact of the Okinawa-based Nordic (O-BN) diet-a low-carbohydrate, high-fiber diet-on these levels after following the diet for 3 months. IAPP, IAPPO-IgA, and total IgA levels were measured in plasma and fecal samples from n = 30 T2D patients collected at baseline, after 3 months of diet, and after additional 4 months of unrestricted diets (a clinical follow-up). The IAPP and IAPPO-IgA levels were significantly lower after 3 months, with the latter also being significantly reduced at the clinical follow-up. The reduction in plasma IAPP and IAPPO-IgA levels correlated with reductions in plasma levels of metabolic and inflammatory markers. Hence, following the O-BN diet for at least 3 months is sufficient to reduce circulating IAPP and IAPPO-IgA levels, which may be principal in managing T2D.

Metformin Prevents Tumor Cell Growth and Invasion of Human Hormone Receptor-Positive Breast Cancer (HR+ BC) Cells via FOXA1 Inhibition.

Women with type 2 diabetes (T2D) have a higher risk of being diagnosed with breast cancer and have worse survival than non-diabetic women if they do develop breast cancer. However, more research is needed to elucidate the biological underpinnings of these relationships. Here, we found that forkhead box A1 (FOXA1), a forkhead family transcription factor, and metformin (1,1-dimethylbiguanide hydrochloride), a medication used to treat T2D, may impact hormone-receptor-positive (HR+) breast cancer (BC) tumor cell growth and metastasis. Indeed, fourteen diabetes-associated genes are highly expressed in only three HR+ breast cancer cell lines but not the other subtypes utilizing a 53,805 gene database obtained from NCBI GEO. Among the diabetes-related genes, FOXA1, MTA3, PAK4, FGFR3, and KIF22 were highly expressed in HR+ breast cancer from 4032 breast cancer patient tissue samples using the Breast Cancer Gene Expression Omnibus. Notably, elevated FOXA1 expression correlated with poorer overall survival in patients with estrogen-receptor-positive/progesterone-receptor-positive (ER+/PR+) breast cancer. Furthermore, experiments demonstrated that loss of the FOXA1 gene inhibited tumor proliferation and invasion in vitro using MCF-7 and T47D HR+ breast cancer cell lines. Metformin, an anti-diabetic medication, significantly suppressed tumor cell growth in MCF-7 cells. Additionally, either metformin treatment or FOXA1 gene deletion enhanced tamoxifen-induced tumor growth inhibition in HR+ breast cancer cell lines within an ex vivo three-dimensional (3D) organoid model. Therefore, the diabetes-related medicine metformin and FOXA1 gene inhibition might be a new treatment for patients with HR+ breast cancer when combined with tamoxifen, an endocrine therapy.

Comparative Screening of the Liver Gene Expression Profiles from Type 1 and Type 2 Diabetes Rat Models.

Experimental animal models of diabetes can be useful for identifying novel targets related to disease, for understanding its physiopathology, and for evaluating emerging antidiabetic treatments. This study aimed to characterize two rat diabetes models: HFD + STZ, a high-fat diet (60% fat) combined with streptozotocin administration (STZ, 35 mg/kg BW), and a model with a single STZ dose (65 mg/kg BW) in comparison with healthy rats. HFD + STZ- induced animals demonstrated a stable hyperglycemia range (350-450 mg/dL), whereas in the STZ-induced rats, we found glucose concentration values with a greater dispersion, ranging from 270 to 510 mg/dL. Moreover, in the HFD + STZ group, the AUC value of the insulin tolerance test (ITT) was found to be remarkably augmented by 6.2-fold higher than in healthy animals (33,687.0 ± 1705.7 mg/dL/min vs. 5469.0 ± 267.6, respectively), indicating insulin resistance (IR). In contrast, a more moderate AUC value was observed in the STZ group (19,059.0 ± 3037.4 mg/dL/min) resulting in a value 2.5-fold higher than the average exhibited by the control group. After microarray experiments on liver tissue from all animals, we analyzed genes exhibiting a fold change value in gene expression <-2 or >2 (p-value <0.05). We found 27,686 differentially expressed genes (DEG), identified the top 10 DEGs and detected 849 coding genes that exhibited opposite expression patterns between both diabetes models (491 upregulated genes in the STZ model and 358 upregulated genes in HFD + STZ animals). Finally, we performed an enrichment analysis of the 849 selected genes. Whereas in the STZ model we found cellular pathways related to lipid biosynthesis and metabolism, in the HFD + STZ model we identified pathways related to immunometabolism. Some phenotypic differences observed in the models could be explained by transcriptomic results; however, further studies are needed to corroborate these findings. Our data confirm that the STZ and the HFD + STZ models are reliable experimental models for human T1D and T2D, respectively. These results also provide insight into alterations in the expression of specific liver genes and could be utilized in future studies focusing on diabetes complications associated with impaired liver function.

Lactoferrin suppresses the progression of colon cancer under hyperglycemia by targeting WTAP/m6A/NT5DC3/HKDC1 axis.

BACKGROUND: Although the relationship between type 2 diabetes (T2D) and the increased risk of colorectal carcinogenesis is widely defined in clinical studies, the therapeutic methods and molecular mechanism of T2D-induced colon cancer and how does hyperglycemia affect the progression is still unknown. Here, we studied the function of lactoferrin (LF) in suppressing the progression of colon cancer in T2D mice, and uncovered the related molecular mechanisms in DNA 5mC and RNA m6A levels. METHODS: We examined the effects of LF (50% iron saturation) on the migration and invasion of colon tumor cells under high concentration of glucose. Then, transcriptomics and DNA methylation profilings of colon tumor cells was co-analyzed to screen out the special gene (NT5DC3), and the expression level of NT5DC3 in 75 clinical blood samples was detected by q-PCR and western blot, to investigate whether NT5DC3 was a biomarker to distinguish T2D patients and T2D-induced colon cancer patients from healthy volunteers. Futhermore, in T2D mouse with xenografted colon tumor models, the inhibitory effects of LF and NT5DC3 protein on colon tumors were investigated. In addition, epigenetic alterations were measured to examine the 5mC/m6A modification sites of NT5DC3 regulated by LF. Utilizing siRNA fragments of eight m6A-related genes, the special gene (WTAP) regulating m6A of NT5DC was proved, and the effect of LF on WTAP/NT5DC3/HKDC1 axis was finally evaluated. RESULTS: A special gene NT5DC3 was screened out through co-analysis of transcriptomics and DNA methylation profiling, and HKDC1 might be a downstream sensor of NT5DC3. Mechanistically, LF-dependent cellular DNA 5mC and RNA m6A profiling remodeling transcriptionally regulate NT5DC3 expression. WTAP plays a key role in regulating NT5DC3 m6A modification and subsequently controls NT5DC3 downstream target HKDC1 expression. Moreover, co-treatment of lactoferrin and NT5DC3 protein restrains the growth of colon tumors by altering the aberrant epigenetic markers. Strikingly, clinical blood samples analysis demonstrates NT5DC3 protein expression is required to direct the distinction of T2D or T2D-induced colon cancer with healthy humans. CONCLUSIONS: Together, this study reveals that lactoferrin acts as a major factor to repress the progression of colon cancer under hyperglycemia, thus, significantly expanding the landscape of natural dietary mediated tumor suppression.