Effet d'un déficit en zinc sur la santé et l'obésité?

[Nutrimuscle-Conseils]

Is There a Link between Zinc Intake and Status with Plasma Fatty Acid Profile and Desaturase Activities in Dyslipidemic Subjects?
by Marija Knez Nutrients 2020, 12(1), 93;

The prevalence of obesity and dyslipidemia has increased worldwide. The role of trace elements in the pathogenesis of these conditions is not well understood. This study examines the relationship between dietary zinc (Zn) intake and plasma concentrations of Zn, copper (Cu) and iron (Fe) with lipid profile indicators, fatty acid composition in plasma phospholipids and desaturase enzyme activities in a dyslipidemic population.

The role of the newly proposed biomarker of Zn status, the linoleic:dihomo-gama-linolenic acid (LA:DGLA) ratio, in predicting Zn status of dyslipidemic subjects has been explored. The study included 27 dyslipidemic adults, 39–72 years old. Trace elements were determined using atomic absorption spectrometry and fatty acid composition by a liquid gas chromatography. Desaturase activities were calculated from product-precursor fatty acid ratios. Dietary data were obtained using 24 h recall questionnaires.

Insufficient dietary intake of Zn, low plasma Zn concentrations and an altered Cu:Zn ratio is related to modified fatty acid profile in subjects with dyslipidemia. Plasma Zn status was associated with obesity. There was no correlation between dietary Zn intake and plasma Zn status. The LA:DGLA ratio was inversely linked to dietary Zn intake. Cu, in addition to Zn, may directly or indirectly, affect the activity of desaturase enzymes.µ

[Nutrimuscle-Conseils]

People with dyslipidemia have inadequate dietary intakes of Zn, low plasma Zn status, and an altered FA composition. The concentrations of plasma Zn were linked to BMI and obesity, and there was no correlation between the dietary Zn intake and plasma Zn status.

The low plasma Zn concentrations were also seen in obese individuals, those with hypertension and type 2 diabetes [57,58].

The highest concentrations of Cu were seen in people with the lowest levels of plasma Zn.

The reduction in plasma Zn levels in this study group could be explained by an increased uptake of Zn by tissues. Additionally, due to the presence of slight inflammation there may be change in the protein Zn-binding capacities

Sixty-five percent of our study sample did not meet dietary Zn requirements, which certainly contributed to low plasma Zn concentrations. Low dietary intake of Zn is found in people with a higher prevalence of coronary risk factors [70]. The bioavailability of Zn from the diet is highly dependent on the phytate: Zn molar ratio, and ratios above 15 are associated with a marked reduction in Zn absorption [53,75]. Dietary data are showing that major sources of Zn in our study group are plant sources (cereals-white and wholemeal bread), legumes and vegetables) with acknowledged high phytate content

Zn dependent alpha2-glycoprotein (ZAG) is an adipokine which stimulates energy expenditure in skeletal muscle and brown adipose tissues resulting in reductions in body weight and TGs

Zn can have an endogenous protective role against dyslipidemia and arteriosclerosis as it can inhibit the oxidation of LDL-C and protect against inflammatory diseases by inhibiting the activation of oxidative stress

The low intake and status of n-3 PUFA has been shown in obese populations and those with metabolic syndrome [61]. Low levels of n-3 PUFA are known to decrease the expression of mitochondrial messenger ribonucleic acid (RNA), which plays a role in a defense against obesity

The highest blood levels of LA in addition to n-3 FA reduced a risk of death for more than 50% [109]. However, the intake of n-3 FAs of participants in this group was below recommended intakes.