Biomonitoring of manganese metal pollution in water and its impacts on biological activities of Biomphalaria alexandrina snail and larvicidal potencies

Metal pollution has many dangerous environmental and human health consequences due to the bioaccumulation in the tissues. The present study aims to measure the bioaccumulation factor of the manganese (Mn) heavy metal in Biomphalaria alexandrina snails' tissues and water samples. The current results showed the concentration of Mn heavy metal in water (87.5 mg/l) and its bioaccumulation factor in Helisoma duryi tissue was higher than that in tissues of Physa acuta and B. alexandrina snails. Results showed that 87.5 mg/l Mn concentration had miracidicidal and cercaricidal activities. Also, this concentration decreased the mean total number of the hemocytes after exposure for 24 h or 48 h, while increasing both the mean mortality and phagocytic indices of the hemocytes of exposed snails. It caused alterations in the cytomorphology of the hemocytes of exposed snails after 24 or 48 h, where the granulocytes had irregular cell membranes and formed pseudopodia. Besides, levels of testosterone (T) and estradiol (E) were increased after exposure to 87.5 mg/l Mn metal compared to the control group. Also, it increased MDA (malonaldehyde) and TAC (total antioxidant capacity) contents, while decreasing SOD (superoxide dismutase). Besides, it caused significant histopathological damages in both hermaphrodite and digestive glands, represented in the degeneration of the gonadal, digestive, secretory cells, and the connective tissues. Therefore, B. alexandrina might be used as a sensitive bioindicator of pollution with Mn heavy metal to avoid ethics rules; besides, they are readily available and large in number.

Hormonal and molecular alterations induced by sub-lethal toxicity of zinc oxide nanoparticles on Oreochromis niloticus

This study was carried out to determine the biochemical and molecular potential effects of Zn-ONPs sub-lethal toxicity on the hormonal profile of Oreochromis niloticus (O. niloticus). One hundred and fifty O. niloticus juvenile female were used in this experiment; Ninety for determination of LC50 and other 60 fish were divided into 3 groups with 20 fish each (two replicate in each group). Group I used as control group whereas other groups treated with 1/20 and 1/30 of LC50 respectively for 4 days. Serum, pituitary gland, hepatic, pancreatic and muscular tissues were obtained for hormonal and molecular evaluation. Serum growth hormone (GH), thyroid stimulating hormone (TSH), triiodothyronine (T3), tetraiodothyronine (T4), follicular stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), testosterone and insulin hormones were significantly decreased with a significant increase in both Adrenocorticosteroid hormone (ACTH) and cortisol levels with no change in serum glucagon levels. On molecular levels there were a significant down regulation in transcriptional levels of GH, Insulin like growth factor I (IGF-I), insulin and Insulin receptor-A (IRA genes. These results suggested that, hormonal and molecular alterations can be used as an early biomarkers for Zn-ONPs toxicity in fish.

Relationships between eating disorder psychopathology, sexual hormones and sexual behaviours

A growing body of evidences demonstrated that sexuality is an important topic in the clinical research of eating disorders (EDs), due to its association with specific psychopathological features, and etiological factors. The present review took into consideration the complex relationship between sexual behaviours, hormonal alterations and EDs psychopathology. Studies pertaining sexual behaviours in EDs were divided into those focusing on sexual dysfunctions, and those related to risky sexual behaviours. The limited number of studies on sexual dysfunctions, reported a controversial association with weight status and hormonal alterations, and a clear relationship with severity of specific psychopathology (e.g. body image disturbance). Risky sexual behaviours have been associated with impulsivity and dissociation, as well as with abnormal stress response. Finally, both restriction and uncontrolled eating have been found to be responsible for several complex metabolic alterations, determining varied sexual and gynecologic problems, such as amenorrhea, hypogonadism, genital vascular problems, infertility, and miscarriage, although it is also possible that alterations in feeding and stress hormones contribute to altered eating behaviour.