Folic Acid Supplementation in Chinese Peri-conceptional Population: Results from the SPCC Study.

OBJECTIVE: To determine the prevalence and determinants of folic acid (FA) supplementation in Chinese couples planning for pregnancy and in women during early pregnancy. METHODS: This was a cross-sectional study based on the Shanghai PreConception Cohort (SPCC) study. Data on FA supplementation and socio-demographic features were collected using questionnaires. Couples visiting clinics for pre-pregnancy examination and pregnant women at < 14 gestational weeks were recruited in Shanghai, China, between March 2016 and September 2018. RESULTS: Among the pregnancy planners, 42.4% (4,710/11,099) women and 17.1% (1,377/8,045) men used FA supplements, while 93.4% (14,585/15,615) of the pregnant women used FA supplements. FA supplement use was higher in female pregnancy planners who were older ( RR: 1.13, 95% CI: 1.08-1.18), had higher education ( RR: 1.71, 95% CI: 1.53-1.92), and were residing in urban districts ( RR: 1.06, 95% CI: 1.01-1.11) of FA supplementation; female pregnancy planners with alcohol consumption ( RR: 0.95, 95% CI: 0.90-0.99) had lower odds of FA supplementation. In early pregnancy, women with higher educational level ( RR: 1.04, 95% CI: 1.03-1.06), who underwent pre-pregnancy examination ( RR: 1.02, 95% CI: 1.01-1.03) had higher odds of using an FA supplement; older aged ( RR: 0.99, 95% CI: 0.98-0.99), and multigravida ( RR: 0.97, 95% CI: 0.96-0.98) had lower odds of FA supplementation. CONCLUSION: Although the majority of pregnant women took FA supplements, more than half of the women planning for pregnancy did not. Urgent strategies are needed to improve pre-conception FA supplementation.

Peroxisomal-proliferator-activated receptor alpha activates transcription of the rat hepatic malonyl-CoA decarboxylase gene: a key regulation of malonyl-CoA level.

MCD (malonyl-CoA decarboxylase), which catalyses decarboxylation of malonyl-CoA, is known to play an important role in the regulation of malonyl-CoA concentration. Recently, it has been observed that the expression of MCD is significantly decreased in the hearts of the PPARalpha (peroxisome-proliferator-activated receptor alpha) (-/-) mice, where the rate of fatty-acid oxidation is decreased by the increased malonyl-CoA level [Campbell, Kozak, Wagner, Altarejos, Dyck, Belke, Severson, Kelly and Lopaschuk (2002) J. Biol. Chem. 277, 4098-4103]. This suggests that MCD may be transcriptionally regulated by PPARalpha. To investigate whether PPARalpha is truly responsible for transcriptional regulation of the rat MCD gene, transient reporter assay was performed in CV-1 cells. The promoter activity was increased by 17-fold in CV-1 cells co-transfected with PPARalpha/retinoid X receptor alpha expression plasmid. In sequence analysis of the promoter region, three putative PPREs (PPAR response elements) were identified, and promoter deletion analysis showed that PPRE2 and PPRE3 were functional. Electrophoretic mobility-shift assays revealed that PPARalpha/retinoid X receptor alpha heterodimer indeed bound to the two PPREs, and the binding specificity of PPARalpha on PPRE was also confirmed by experiments with mutated oligonucleotides. These results indicate that the elements behaved as a responsive site to PPARalpha activation. MCD mRNA levels in WY14643-treated rat hepatoma cells as well as in the liver of fenofibrate-fed Otsuka Long-Evans Tokushima fatty rats were also found to be increased, suggesting that PPARalpha can activate the rat hepatic MCD transcription by binding to the PPREs in the promoter. We propose that MCD performs an important role in understanding the regulatory mechanism between activated PPARalpha and fatty-acid oxidation by altering the malonyl-CoA concentration.

Carnitine palmitoyltransferase-1 (CPT-1) activity stimulation by cerulenin via sympathetic nervous system activation overrides cerulenin's peripheral effect.

To clarify the paradoxic effects of cerulenin, namely its in vitro inhibitory effects on fat catabolism and its in vivo reduction of fat mass, we studied the in vivo and in vitro effects of cerulenin on carnitine palmitoyltransferase-1 (CPT-1) activity, the rate-limiting enzyme of fatty acid oxidation. A single ip injection of cerulenin significantly reduced body weight and increased core temperature without significantly reducing food intake. In situ hybridization study revealed that a single injection of cerulenin did not affect the expression of orexigenic neuropeptide mRNA. Cerulenin's effect on CPT-1 activity was biphasic in the liver and muscle: early suppression during the first 1 h and late stimulation in the 3-5 h after ip treatment. In vitro cerulenin treatment reduced CPT-1 activity, which was overcome by cotreating with catecholamine. Intracerebroventricular injection of cerulenin increased CPT-1 activity significantly in soleus muscle, and this effect was sustained for up to 3 h. Pretreatment with alpha-methyl-p-tyrosine inhibited the cerulenin-induced increase in core temperature and the late-phase stimulating effect of cerulenin on CPT-1 activity. In adrenalectomized mice, cerulenin also increased the activity. In vivo cerulenin treatment enhanced muscle CPT-1 activity in monosodium glutamate-treated arcuate nucleus lesioned mice but not in gold thioglucose-treated ventromedial hypothalamus lesioned mice. These findings suggest that cerulenin-induced late-phase stimulating effects on CPT-1 activity and energy expenditure is mediated by the activation of innervated sympathetic nervous system neurons through the firing of undefined neurons of the ventromedial hypothalamus, rather than the arcuate nucleus.

The different mechanisms of insulin sensitizers to prevent type 2 diabetes in OLETF rats.

OBJECTIVE: To investigate the effects of pioglitazone and metformin treatment during pre-diabetic period for the prevention of diabetes in a rat model. METHODS: OLETF rats aged 18-weeks, were treated with pioglitazone (10 mg/kg/day) and metformin (300 mg/kg/day) for 10 weeks from their pre-diabetic period. We measured weight, lipid profiles, fat distribution, glucose tolerance, and pancreatic insulin content. RESULTS: Prominent weight gain (mostly subcutaneous fat area) was observed in the pioglitazone-treated OLETF (O-P) rats versus significant weight loss was observed in the metformin-treated OLETF (O-M) rats. Pioglitazone reversed the serum triglyceride (TG) and FFAs levels to normal (TG 0.46 +/- 0.04 vs 0.88 +/- 0.05 mmol/l in LETO). At the age of 28 weeks, the O-P rats showed completely normal glucose tolerance, and the glucose disposal rate (GDR) was markedly improved (25.6 +/- 0.4 vs 20.6 +/- 0.5 mg/min/kg in O-C, p < 0.05). The O-M rats also showed an improved fasting glucose and GDR level, but not as much as those with O-P rats. The pancreas insulin contents were much improved in the O-P rats (22.9 +/- 1.2 vs 18.8 +/- 1.3 nmol/pancreas in O-M rats, p < 0.05) with histological improvement. CONCLUSION: The pre-diabetic treatment with pioglitazone, despite significant weight gain, completely prevents to develop diabetes and enhances beta cell function with preservation of islet cell changes. Metformin treatment was also effective, but mainly by ameliorating the insulin resistance with marked reduction in body weight. The reversal of dyslipidaemia and the fat redistribution might contribute to the greater improvement of pioglitazone treatment compared to metformin in OLETF rats.

Safety and efficacy of adeno-associated viral vector-mediated insulin gene transfer via portal vein to the livers of streptozotocin-induced diabetic Sprague-Dawley rats.

BACKGROUND: Previous studies demonstrating the efficacy of insulin gene therapy have mostly involved use of adenoviral vectors or naked DNA to deliver the insulin gene. However, this procedure may not guarantee long-term insulin production. To improve the performance, we prepared recombinant adeno-associated viral vectors (rAAV) harboring the gene encoding a furin-modified human insulin under the cytomegalovirus (CMV) promoter [rAAV-hPPI(F12)]. METHODS: Streptozotocin (STZ)-induced diabetic Sprague-Dawley rats were used as a diabetic animal model. The levels of blood glucose, insulin, and HbA1c were measured to test the effect. An intraperitoneal glucose tolerance test was performed to test the capability of blood glucose disposal. Immunohistochemical staining and Northern blot analyses were performed to survey the expression pattern of the therapeutic insulin gene. RESULTS: STZ-induced diabetic Sprague-Dawley rats infused via the portal vein with rAAV-hPPI(F12) produced human insulin and after a 6-h fast were normoglycemic for over 90 days post-treatment, whereas diabetic rats treated with recombinant adenoviral vector harboring the hPPI(F12) gene [rAV-hPPI(F12)] were normoglycemic only for days 3 to 13 post-treatment. Insulin mRNA was detected mainly in the liver of the rAAV-hPPI(F12)-treated diabetic rats. The glucose tolerance capability of the rAAV-hPPI(F12)-treated diabetic rats was comparable to that of non-diabetic rats, even without injection of recombinant insulin. Furthermore, blood HbA1c concentrations in rAAV-hPPI(F12)-treated diabetic rats were reduced to almost the normal level. Importantly, studies of rAV or rAAV vector-dependent side effects on the targeted liver strongly suggested that only rAAV treatment caused no side effects. CONCLUSIONS: These results demonstrate that our rAAV-mediated in vivo insulin gene therapy provides safer maintenance of the insulin gene expression required for long-term and thus more effective blood glycemic control.

Left-ventricular diastolic dysfunction may be prevented by chronic treatment with PPAR-alpha or -gamma agonists in a type 2 diabetic animal model.

OBJECTIVES: The aim of this study was to determine whether the peroxisome proliferator-activated receptor (PPAR) ligands could prevent left-ventricular diastolic dysfunction (LVDD) in rats with advanced diabetes. In addition, this study examined whether the activity of malonyl-CoA decarboxylase (MCD), which is an enzyme related to the degradation of malonyl-CoA that is known to regulate the fatty acid metabolism, is changed by the diabetic state itself or by treatment with the PPAR ligands. METHODS: Male Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of type 2 diabetes, aged 28 weeks, were divided into 3 groups: the untreated, pioglitazone-treated (10 mg/kg/d), and fenofibrate-treated (150 mg/kg/d) groups. The rats were treated for 10 weeks. Male Long-Evans Tokushima Otsuka (LETO) rats were used as nondiabetic control. Doppler echocardiography and measurements of the MCD activity at the myocardium were performed. RESULTS: At the age of 38 weeks, the OLETF rats treated with either pioglitazone or fenofibrate showed an improvement in the plasma glucose levels after glucose loading as well as an improvement in the fasting plasma insulin, triglyceride, and FFA levels compared to the untreated OLETF rats. The untreated OLETF rats showed a prolonged deceleration time of the E-wave (DTE) (74.3 +/- 3.7 vs LETO, 56.3 +/- 3.8 ms, P < 0.05) and a reduced ratio of the peak early diastolic velocity wave to the late diastolic wave (E/A ratio) (1.25 +/- 0.06 vs LETO 1.54 +/- 0.08, P < 0.05). Pioglitazone treatment in the OLETF rats improved the DTE (51.6 +/- 1.7 ms, P < 0.05), and the fenofibrate treatment also improved the DTE (61.4 +/- 4.3 ms, P < 0.05) and E/A ratio (1.57 +/- 0.05, P < 0.05) compared to the untreated OLETF rats. The parameters related to the systolic function did not change among the groups at both pre- and post-treatments. The MCD activity of the myocardium was remarkably lower in the OLETF rats compared to the LETO rats (3.26 +/- 0.38 vs 7.76 +/- 0.84 nmol/min/mg protein, P < 0.05). The pioglitazone and fenofibrate treatments resulted in an increase in the MCD activity compared to that in the untreated rats (7.20 +/- 0.74 and 8.33 +/- 0.83 nmol/min/mg protein, P < 0.05, respectively). CONCLUSIONS: The PPAR-alpha or -gamma agonists prevented LVDD in the advanced diabetic rat hearts, possibly through an improvement in the fatty acid metabolism in the myocardium or a correction of the hyperglycemia and/or hyperlipidemia.