Metabolic syndrome and endocrine status in HIV-infected transwomen.

BACKGROUND: HIV-infected transwomen face multiple specific issues. Economic and social marginalization, sex work, substance abuse, hormonal consumption and silicone injection may affect the course of HIV infection and lead to metabolic and endocrine complications. METHODS: A matched case-control study was performed between 2013 and 2015 in a University Hospital and compared metabolic syndrome (MetS), thyroid and adrenal functions in HIV-infected transwomen (i.e. cases) and cisgender HIV-infected men (i.e. controls) matched for age and antiretroviral therapy. The interaction between hormonal consumption, the course of HIV infection and antiretroviral therapy was also studied. Clinical and biological data (CD4 cell count, HIV RNA load, antiretroviral plasma drug concentration, HDL, triglycerides, glucose, cortisol, thyroid stimulating hormone, free thyroxine, prolactine) were measured. RESULTS: A total of 292 HIV-infected patients (100 cases and 192 controls) were prospectively included. There was no difference between the two populations in terms of frequency of MetS, but subclinical hypothyroidism and adrenal insufficiency were more frequent in cases than in controls with, respectively, 12 vs. 3% (P < 0.002) for hypothyroidism and 20 vs. 8% (P < 0.001) for adrenal insufficiency. Prolactinemia, only performed in transwomen, was often elevated (21%) but rarely confirmed as true active hyperprolactinemia (monomeric form) (3%). Although hormonal intake was frequent among transwomen (31%), no impact on antiretroviral bioavailability and efficacy was detected. CONCLUSION: In this study, no increase in the prevalence of MetS was detected in HIV-infected transwomen patients. In contrast, adrenal and thyroid functions abnormalities were frequent and should be systematically assessed in this population. No impact of hormonal intake on antiretroviral bioavailability and efficacy was detected.

Skin collagen pentosidine and fluorescence in diabetes were predictors of retinopathy progression and creatininemia increase already 6years after punch-biopsy.

OBJECTIVE: Advanced glycation end products (AGEs) of collagens appear to contribute to microvascular complications in diabetes. Do high concentrations of AGEs in skin collagen predict accelerated progression of these complications after 6 years and indicate the need for tighter anti-diabetic treatment? DESIGN AND METHODS: We measured two AGE parameters in collagen extracted from skin punch-biopsies: pentosidine and fluorescence at 370/440nm, as markers and predictors of microvascular complications, in 30 patients with diabetes (14 type-1, 16 type-2) without renal insufficiency, and in age- and gender-matched normoglycemic controls, followed at Hôtel-Dieu in Paris. RESULTS: At the time of biopsy, marked increases in pentosidine (p=0.0014) and fluorescence (p=0.0001) expressed per collagen hydroxyproline, were found in the patients with diabetes versus the controls. A significant effect of age was found for pentosidine, but not fluorescence, measurements in the normoglycemic controls. Therefore pentosidine but not fluorescence results were corrected for age in the patients. Pentosidine and fluorescence were correlated with diabetes duration. Fluorescence was significantly dependent on retinopathy presence and score in type-1 and type-2 diabetes, whereas pentosidine was not. Fluorescence was correlated with microalbuminuria only in type-1 diabetes. Neither fluorescence nor pentosidine were correlated with creatininemia. Already six years after biopsy, retinopathy score progression and creatininemia increase were significantly correlated with initial pentosidine and fluorescence measurements. CONCLUSIONS: These AGEs are good predictors of progression of microvascular complications and appear to be pathogenic. High skin concentrations of AGEs should induce tighter anti-diabetic treatment.

Correlations between urinary excretion of catecholamines and electrocardiographic parameters of vagal hyperreactivity in infants with fainting spells. Implication of sympathetic hypotonia?

BACKGROUND: Vagal hyperreactivity (VHR) is a frequent etiology of infant fainting spells; but it is sometimes difficult to diagnose. A biochemical test would therefore be useful, especially as the oculocardiac reflex (OCR) test innocuity is not absolute. AIMS: To evaluate urinary excretions of norepinephrine, epinephrine and dopamine as markers for vagal hyperreactivity. METHODS: During check-up of 55 infants from 0.5 to 11 months of age, for discomfort episodes, including OCR and Holter recording, 24h urinary assays of total norepinephrine, epinephrine and dopamine were carried out to evaluate sympathetic activity. RESULTS: Epinephrine and norepinephrine urinary excretions were negatively correlated with VHR intensity, as measured by the OCR ECG parameters: RRmax, % cardiac deceleration and minimal frequency; dopamine excretion was not. When RRmax(OCR) was greater or equal to 800 ms, epinephrine urinary excretion tended to be less or equal to 9 nmol/mmol creatinine and norepinephrine excretion less or equal to 190 nmol/mmol creatinine. CONCLUSION: A delay in maturation of the sympathetic system and/or adrenomedullary glands with low secretion of norepinephrine and epinephrine inducing a desequilibrium of the sympathetic/parasympathetic balance may contribute to the fainting spells observed with VHR. Epinephrine and norepinephrine urinary excretions may provide informative complementary noninvasive markers for VHR.

[Inhibition of advanced glycation by flavonoids. A nutritional implication for preventing diabetes complications?]. / Inhibition de la glycation avancée par les flavonoïdes. Implication nutritionnelle dans la prévention des complications du diabète?

Advanced glycation of collagens contributes to development of micro- and macrovascular complications in diabetes. Since flavonoids are potent natural antioxidants, it was interesting to examine their effect on the formation of a cross-linking advanced glycation endproduct, pentosidine, in collagen incubated with glucose. Monomeric flavonoids (25 and 250 microM) markedly reduced pentosidine/hydroxyproline values in a concentration- and structure-dependent manner. Procyanidin oligomers from grape seed were more active than pine bark procyanidin oligomers. Oligomers are known to be cleaved into monomers in the gastric milieu and monomeric flavonoids to be absorbed and recovered at micromolar concentrations (with a long plasmatic half-life) in extracellular fluids, in contact with collagens. In conclusion, flavonoids are very potent inhibitors of pentosidine formation in collagens, active at micromolar concentrations; these concentrations might be achieved in plasma of diabetic patients after oral intake of flavonoids.

Flavonoids inhibit the formation of the cross-linking AGE pentosidine in collagen incubated with glucose, according to their structure.

BACKGROUND: Glycoxidation of collagens contributes to development of vascular complications in diabetes. AIM OF THE STUDY: Since flavonoids are potent antioxidants present in vegetal foods, it was interesting to examine their effect on the formation of a cross-linking advanced glycation endproduct, pentosidine, in collagens. METHODS: Collagen was incubated with glucose (250 mM), in the presence of different flavonoids. Pentosidine was measured by HPLC, hydroxyproline colorimetrically. RESULTS: Monomeric flavonoids (25 and 250 microM) markedly reduced pentosidine/hydroxyproline values in a concentration- and structure-dependent manner. In decreasing order of their specific inhibitory activity, they rank as follows: myricetin > or = quercetin > rutin > (+)catechin > kaempferol. Thus 3'-OH or 4-oxo + Delta(2-3) increase the inhibitory activity; conjugation by Rha-Glc on 3-OH decreases it. Procyanidin oligomers from grape seed were more active than pine bark procyanidin oligomers: this may be related to the galloyl residues present in grape seed oligomers only. Procyanidin oligomers are known to be cleaved into monomers in the gastric milieu and monomeric flavonoids to be absorbed and recovered at micromolar concentrations (with a long plasmatic half-life) in extracellular fluids, in contact with collagens. CONCLUSION: Flavonoids are very potent inhibitors of pentosidine formation in collagens. They are active at micromolar concentrations; these might be achieved in plasma of diabetic patients after oral intake of natural flavonoids.