A Novel Splice Site Variant in the LDLRAP1 Gene Causes Familial Hypercholesterolemia

Background:FH, a hereditary disorder, is caused by pathogenic variants in the LDLR, APOB, and PCSK9 genes. This study has assessed genetic variants in a family, clinically diagnosed with FH. Methods:A family was recruited from MASHAD study in Iran with possible FH based on the Simon Broom criteria. The DNA sample of an affected individual (proband) was analyzed using WES, followed by bioinformatics and segregation analyses. Results:A novel splice site variant (c.345-2A>G) was detected in the LDLRAP1 gene, which was segregated in all affected family members. Moreover, HMGCR rs3846662 g.23092A>G was found to be homozygous (G/G) in the proband, probably leading to reduced response to simvastatin and pravastatin. Conclusion:LDLRAP1 c.345-2A>G could alter the PTB, which acts as an important part of biological pathways related to lipid metabolism. Key Words: Genetic research, LDLRAP1, Hypercholesterolemia, Hydroxymethylglutaryl-CoA Reductase Inhibitors     

Live Spirulina (Arthrospira platensis) as a growth and immunity promoter for Nile tilapia, Oreochromis niloticus (L.), challenged with pathogenic Aeromonas hydrophila

The use of antibiotics to control fish disease is one of the constraints in tilapia farming. Hence, the use of probiotic and live organisms as alternative strategies has received much more attention. This study was undertaken to evaluate the use of Spirulina (Arthrospir platensis) as a growth and immunity promoter for Nile tilapia, Oreochromis niloticus (L.). Fish (1.88 g) were randomly distributed at 20 fish per 100 L aquarium and fed a diet containing either 0.0, 1.25, 2.5, 5.0, 7.5 or 10.0 g Spirulina kg^?1 diet for 12 weeks. After the feeding trial, fish of each treatment were challenged by pathogenic Aeromonas hydrophila, which was given by an interperitoneal injection, and they were kept under observation for 10 days to record any abnormal clinical signs and the daily mortality rate. The growth‐promoting influence of Spirulina was observed with fish, and the optimum growth and feed utilization were obtained at 5.0 g Spirulina kg^?1 diet. No significant changes were observed in fish survival among the different treatments. Spirulina supplementation improved the protein and lipid contents in fish bodies without significant differences among them, especially when fed 2.5–10.0 g kg^?1 diet, but no significant differences in the moisture and ash contents were observed among different treatments. The physiological parameters were improved when fish were fed a Spirulina‐enriched diet. However, the highest red blood cells, white blood cells and nitro blue tetrazolium values were obtained at 5.0–10.0 g Spirulina kg^?1 diet; meanwhile, the lowest value was obtained in the control. Total fish mortality due to A. hydrophila infection decreased with an increase in the Spirulina level in fish diets. These results indicate that Spirulina supplement is promising as an alternative method to antibiotics for disease prevention in tilapia aquaculture, and the optimum level of Spirulina in the fish diet should be 5.0–10.0 g kg^?1 diet.     

Effect of dietary protein regime during the growing period on growth performance, feed utilization and whole-body chemical composition of Nile Tilapia, Oreochromis niloticus (L.)

This study was conducted to evaluate the effect of various dietary protein regimes on growth performance, feed utilization and whole-body chemical composition of Nile tilapia, Oreochromis niloticus (L.). Twenty cages (1 m³ each) were randomly allocated to a four-replicate experiment to represent five treatments (T1–T5) where fish were randomly stocked at a rate of 50 fish (1.5–2.2 g) per cage. Fish in T1–T5 fed on a 45% crude protein (CP) diet for the first 4 weeks. In T1, T2 or T3 fish fed on 45%, 35% or 25% CP diets for the last 8 weeks respectively. In T4 fish fed 35% CP diet for the second 4 weeks followed by 25% CP diet for the last 4 weeks and in T5 fish fed 25% CP diet for the second 4 weeks followed by 35% CP diet for the last 4 weeks. Diets were offered to satiation and provided manually twice a day in the morning and in the afternoon, 6 days a week. The optimum fish growth and feed utilization were obtained at T1, T2 and T4. Protein efficient ratio and apparent protein utilization were lower at T1 and T2 than those of T3–T5. On the other hand, no significant changes in energy utilization were observed among the different treatments. There were no major changes in the carcass composition except in ash content, which was higher in T3 and T5 only. This study recommended that the dietary protein regime is an important management in tilapia culture, and the protein level could be reduced from 45% to 35% then to 25% on increasing the fish size.     

Capability of some agricultural wastes for removing some heavy metals from polluted water stocked in combination with Nile tilapia,Oreochromis niloticus (L.)

Heavy metal (HM) pollution is one of the major problems that adversely affect the aquatic ecosystem and inhabiting biota. Heavy metals adsorption by low-cost adsorbents is one of the techniques used for HM removing from polluted water. In the present study, agricultural wastes (AW), i.e., rice straw, sugarcane bagasse, and maize stalks, were washed with distilled water, dried in a dry-oven, cut into small pieces (<0.5 cm long), and immersed at 1.0 g/L in aquaria containing synthetic mixture of lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn). Nile tilapia, Oreochromis niloticus (L.), fingerlings (25.2 ± 0.88 g) were stocked at a density of ten fish per 100-L aquarium for 72 h, during which fish were fed on a fish diet containing 25% crude protein ad libitum twice daily. Samples of water, AW, and fish were collected at different times to determine HM concentrations. The HM removal from polluted water was depending on the type of the metal ions, AW, and the contact time. However, HM concentrations in aquaria waters of all AW treatments decreased significantly by increasing contact time up to 24 h after which their concentrations were almost the same. Concentrations of waterborne Pb, Cd, Cu, and Zn in AW-containing aquaria were significantly lower than those of AW-free aquaria. The presence of any AW reduced significantly HM concentrations. In AW-free aquaria, HM-exposed fish accumulated more HM in their body than those reared in AW-containing aquaria. The results of this experiment showed that all AW had the capability to remove HM levels from the polluted water and reduce their bioaccumulation in fish body. However, rice straw was the more efficient adsorbent for all metals.