Caloric restriction (CR) reduces the risk of age-related diseases in numerous species, including humans. CR’s metabolic effects, including decreased adiposity and improved insulin sensitivity, are important for its broader health benefits; however, the extent and basis of sex differences in CR’s health benefits are unknown. We found that 30% CR in young (3-month-old) male mice decreased fat mass and improved glucose tolerance and insulin sensitivity, whereas these effects were blunted or absent in young females. Females’ resistance to fat loss was associated with decreased lipolysis, energy expenditure and fatty acid oxidation, and increased postprandial lipogenesis, compared to males. The sex differences in glucose homeostasis were not associated with differential glucose uptake but with altered hepatic ceramide content and substrate metabolism: compared to CR males, CR females had lower TCA cycle activity and higher blood ketone concentrations, a marker of hepatic acetyl-CoA content. This suggests that males use hepatic acetyl-CoA for the TCA cycle whereas in females it accumulates, stimulating gluconeogenesis and limiting hypoglycaemia during CR. In aged mice (18-months old), when females are anoestrus, CR decreased fat mass and improved glucose homeostasis similarly in both sexes. Finally, in a cohort of overweight and obese humans, CR-induced fat loss was also sex- and age-dependent: younger females (45 years) this sex difference was absent. Collectively, these studies identify age-dependent sex differences in the metabolic effects of CR and highlight adipose tissue, the liver and oestrogen as key determinants of CR’s metabolic benefits. These findings have important implications for understanding the interplay between diet and health, and for maximising the benefits of CR in humans.

Study Objectives: Diabetes mellitus per se and its related therapy have been frequently associated with an increased risk of developing dementia. However, studies that explored the risk of dementia from the use of the novel oral antidiabetic medication dipeptidyl peptidase 4 inhibitor (DPP-4i) have been limited, especially in Asian populations. The present study aimed to determine the effect of DPP-4i on the subsequent risk of dementia among patients with type 2 diabetes (T2D) in Taiwan. Methods: This study utilized data from the Longitudinal Health Insurance Database between 2008 and 2015. We enrolled 2903 patients aged ≥50 years, who were on DPP-4i for a diagnosis of T2D and had no dementia. A total of 11,612 subjects were included and compared with a propensity score-matched control group who did not use DPP-4i (non-DPP-4i group). Survival analysis was performed to estimate and compare the risk of dementia—including Alzheimer’s disease, vascular dementia, and other dementia types—between the two groups. Results: Both groups had a mean age of 68 years, had a preponderance of women (61.8%), and were followed up for a mean duration of 7 years. The risk of all-cause dementia was significantly lower in the DPP-4i group than in the non-DPP-4i group (hazard ratio (HR) 0.798; 95% confidence interval (CI) 0.681–0.883; p < 0.001), with a class effect. This trend was particularly observed for vascular dementia (HR 0.575; 95% CI 0.404–0.681; p < 0.001), but not in Alzheimer’s disease (HR 0.891; 95% CI 0.712–1.265; p = 0.297). The Kaplan–Meier analysis showed that the preventive effect on dementia was positively correlated with the cumulative dose of DPP-4i. Conclusions: DPP-4i decreased the risk of dementia with a class effect, especially vascular dementia, but not in Alzheimer’s disease. Our results provide important information on the drug choice when managing patients with T2D in clinical practice.

Background: Patients with diabetes have a relatively high risk of fracture due to osteoporosis. However, the risk of osteoporosis associated with the use of oral hypoglycemic drugs and dipeptidyl peptidase-4 inhibitor (DPP-4i) by patients with diabetes is unclear. This study aimed to explore the effect of DPP-4i on the risk of osteoporosis in Taiwanese patients with type 2 diabetes mellitus (T2DM). Methods: This study enrolled 6339 patients on DPP-4i (DPP-4i group) and 25 356 patients without DPP-4i (non-DPP-4i group). They were matched by 1:4 propensity score matching, using confounding variables including sex, age, comorbidities, medication, and index year. Cox proportional hazards analysis was used to compare hospitalization and mortality during an average follow-up period of 7 years. Results: The mean age of patients in the two groups was 66 years. Men were slightly higher in number (51.79%) than women. At the end of the follow-up period, 113 (0.36%) patients had osteoporosis, of which 15 (0.24%) were in the case group and 98 (0.39%) in the control group. The risk of all-cause osteoporosis was significantly lower in the DPP-4i group than in the non-DPP-4i group (adjusted hazard ratio [HR] 0.616; 95% confidence interval [CI] 0.358–0.961; p = 0.011). Kaplan–Meier analysis showed that the preventive effect on osteoporosis was positively correlated with the cumulative dose of DPP-4i (log-rank, p = 0.039) with the class effect. Conclusion: Compared with not using DPP-4i, the use of DPP-4i in Taiwanese T2DM patients was associated with a lower risk of osteoporosis due to the class effect, and the preventive effect was dose-dependent. However, larger prospective studies are needed to validate this finding and to explore the possible mechanism of the preventive effect of DPP-4i.

Patients with diabetes are at increased risk of cancer development and osteoporosis. Metformin is an effective agent for diabetes management. Epidemiological studies have identified an association between metformin use and cancer prevention. This article outlines the potential for metformin to attenuate the rate of osteoporosis in diabetic patients with carcinoma in situ (CIS). From the National Health Insurance Research Database of Taiwan, 7827 patients with diabetes with CIS who were receiving metformin therapy were selected, along with 23,481 patients as 1:3 sex-, age- and index year-matched controls, who were not receiving metformin therapy. A Cox proportional hazard analysis was used to compare the rate of osteoporosis during an average of 15-year follow-up. Of the subjects who were enrolled, 801 (2.56%) had osteoporosis, including 168 from the metformin group (2.15%) and 633 from the without metformin group (2.70%). The metformin group presented a lower rate of osteoporosis at the end of follow-up (p = 0.009). The Cox proportional hazard regression analysis revealed a lower rate of osteoporosis for the metformin group (adjusted hazard ratio of 0.820; 95% confidence interval = 0.691–0.972, p = 0.022). Diabetic patients with CIS under metformin therapy presented lower osteoporosis rate than those who were not receiving metformin therapy.

Type 2 diabetes mellitus (T2DM) is an independent risk factor of knee osteoarthritis (KOA). This study was mainly based on data from the Taiwan National Health Insurance Database. Using big data analysis, we showed that glucagon-like peptide-1 receptor agonist (GLP-1RA) treatment is helpful for patients with T2DM who have a lower risk of KOA or total knee replacement (TKR). A total of 35,762 patients with T2DM were included in this study. We divided these patients into 988 patients with T2DM without KOA and 372 patients with T2DM with KOA who received GLP-1RA treatment and those who did not receive GLP-1RA treatment. The patients were matched for sex, age, and inclusion date by 1:1 propensity score, which was included in the control group. Cox proportional hazards analyses were performed to compare KOA risk and TKR rate during a maximum follow-up period of 5 years. There were 1976/744 patients with T2DM without/with KOA who received and did not receive GLP-1RA treatment, including 1052/322 men (53.24/43.28%) and 924/422 women (46.76/56.72%). At the end of follow-up, there were 46/39 (4.66/10.48%) patients with T2DM without/with KOA who received GLP-1RA treatment and underwent KOA/TKR were lower than those without GLP-1RA treatment 87/70 (8.81/18.82%). Cox proportional hazard regression analysis showed a lower rate of KOA/TKR among patients with GLP-1RA treatment (adjusted hazard ratio [HR] = .852; 95% confidence interval [CI] = .784–.930, P < .001/ adjusted HR = .913; 95% CI = .885–.977, P = .015, respectively). Kaplan–Meier analysis showed that the cumulative risk of KOA/TKR in patient with/without GLP-1RA was significantly different (log-rank test, P < .001/P < .001, respectively). This study aimed to provide clinicians with the option of GLP-1RA as a treatment for patients with T2DM with or without KOA to reduce the risk of KOA or TKR among such patients.

Bone marrow adipose tissue (BMAT) is a unique fat depot. It has distinct metabolic–endocrine functions and negatively correlates with bone mineral density, increasing with ageing and osteoporosis. Intriguingly, BMAT also expands during caloric restriction (CR), a lifespan-extending dietary intervention that also promotes bone loss; however, whether BMAT is a cause or consequence of this remains unclear. To address this, we studied 9-week-old male and female C57BL/6NCrl mice subjected to 30% CR for 1, 2, 4, or 6 weeks. Bone structure and BMAT volume were quantified by micro-computed tomography using a spatial method that precisely maps BMAT within bones. CR-induced BMAT expansion was site-specific, being greater in tibiae than femora and absent in humeri. Surprisingly, CR increased distal tibial BMAT despite prior suggestions that this BMAT region resists such environmental modulation. Expansion was also duration-dependent, plateauing after 4 weeks, and region-specific, particularly in the tibial metaphysis, femoral metaphysis, and the distal tibia. Similarly, CR altered trabecular and cortical bone in time-, region-, and sex-dependent ways, with BMAT levels more tightly associated with trabecular than cortical changes. CR also increased adiponectin, corticosterone, and ketones, while decreasing leptin, IGF-1, and insulin, in a sex- and/or duration-dependent manner. Metabolic phenotyping demonstrated that BMAT expansion was not associated with altered glucose tolerance, body mass, total fat mass, or fat percentage but correlated with energy deficit and systemic lipid mobilisation. Together, our findings highlight the complex interplay between BMAT expansion, skeletal remodelling, and metabolic homeostasis, providing new insights into BMAT formation and function and the health benefits of CR.