ABSTRACT
Background Vitamin D (VD) is the sunshine vitamin. Its deficiency is widely spread worldwide and is implicated in various health problems that have serious financial, mental, and physical health burdens. In Libya, it also has a high incidence as many studies have been conducted on this issue, but the exact situation of VD deficiency in the southern region of Libya remains unclear. Aim The aim of this study is to investigate the frequency of VD deficiency and calcium status among females of reproductive age in Wadi Etba (located in the southern region of Libya). Material and methods This study included 622 females aged 20-40 years attending the Rural Hospital and Private Clinics in Wadi Etba for various health issues during the last five years. The study population was further subdivided into two age groups; 20-30 years and 31-40 years. VD and calcium were measured to determine the VD status among the study population. Results In general, 489 females had sub-optimal VD (<30 ng/mL), representing 78.6% of the total subjects. Normal VD levels were represented only by 133 subjects (21.4%). VD deficiency was represented by 354 subjects (57%) of the total subjects. A total of 232 (37%) subjects were VD-deficient females (18.3 ± 5.5 ng/ml), 122 subjects (20%) were considered poor (severe deficient, VD <10 ng/ml) represented with a mean serum VD of 8.2 ± 0.6. Furthermore, deficiency cases dominated the older age group. Regarding calcium (Ca+2) levels, 31% had lower than the normal range, 68% had normal range, and only 1% showed high Ca+2 levels. On the other hand, there was no correlation between serum levels of VD and Ca+2 levels. Conclusion VD deficiency has become a widespread condition in the southern region of Libya. Therefore, we recommended making lifestyle changes, including extending the exposure time to the sunlight radiation, fortifying foods and drinks with VD, and taking supplementary doses of VD to reduce the high incidence of VD deficiency.
ABSTRACT
Decorin, a small leucine-rich proteoglycan, regulates extracellular matrix organization, growth factor-mediated signaling, and cell growth. Because decorin may directly modulate immune responses, we investigated its role in a mouse model of contact allergy (oxazolone-mediated delayed-type hypersensitivity [DTH]) in decorin-deficient (Dcn(-/-)) and wild-type mice. Dcn(-/-) mice showed a reduced ear swelling 24 h after oxazolone treatment with a concurrent attenuation of leukocyte infiltration. These findings were corroborated by reduced glucose metabolism, as determined by (18)fluordeoxyglucose uptake in positron emission tomography scans. Unexpectedly, polymorphonuclear leukocyte numbers in Dcn(-/-) blood vessels were significantly increased and accompanied by large numbers of flattened leukocytes adherent to the endothelium. Intravital microscopy and flow chamber and static adhesion assays confirmed increased adhesion and reduced transmigration of Dcn(-/-) leukocytes. Circulating blood neutrophil numbers were significantly increased in Dcn(-/-) mice 24 h after DTH elicitation, but they were only moderately increased in wild-type mice. Expression of the proinflammatory cytokine TNF-α was reduced, whereas syndecan-1 and ICAM-1 were overexpressed in inflamed ears of Dcn(-/-) mice, indicating that these adhesion molecules could be responsible for increased leukocyte adhesion. Decorin treatment of endothelial cells increased tyrosine phosphorylation and reduced syndecan-1 expression. Notably, absence of syndecan-1 in a genetic background lacking decorin rescued the attenuated DTH phenotype of Dcn(-/-) mice. Collectively, these results implicated a role for decorin in mediating DTH responses by influencing polymorphonuclear leukocyte attachment to the endothelium. This occurs via two nonmutually exclusive mechanisms that involve a direct antiadhesive effect on polymorphonuclear leukocytes and a negative regulation of ICAM-1 and syndecan-1 expression.
