Serum homocysteine level and eye involvement in Egyptian patients with Behçet’s disease

Plasma Homocysteine in Behcet's Disease: A Systematic Review and Meta-Analysis

AIM

 To evaluate the relevance of plasma homocysteine (HC) in Behcet's disease (BD) and its clinical manifestations.

METHODS

 Systematic review of EMBASE and PubMed databases according to PRISMA guidelines from inception to July 2021; random-effects meta-analyses for continuous outcomes.

RESULTS

 The search strategy retrieved 48 case-control (2,669 BD and 2,245 control participants) and 5 cohort studies (708 BD participants). Plasma HC was higher in BD than in controls (p < 0.0001) with wide heterogeneity (I2  = 89.7%) that remained unchanged after sensitivity analysis according to year of article publication, age of BD participants, study size, study quality, method of HC determination, and male/female ratio >1.5; some pooled ethnicities explained a small part of the heterogeneity (I2  = 16.3%). Active BD participants had higher HC than inactive ones (p < 0.0001), with moderate heterogeneity (I2  = 49.2%) that disappeared after removal of an outlier study with very high disease activity. BD participants with any vascular involvement had higher HC than those without (p < 0.0001) with wide heterogeneity (I2  = 89.7%); subgroup analysis on venous thrombosis only changed neither effect size (p < 0.0001) nor heterogeneity (I2  = 72.7%). BD participants with ocular involvement had higher HC than those without (p < 0.0001) with moderate heterogeneity (I2  = 40.3%).

CONCLUSION

 Although causality cannot be inferred, the consistency of the elevation of plasma HC in BD, particularly in patients with active disease, with vascular and ocular involvement suggests an intrinsic involvement of HC in these clinical manifestations.

Ameliorative effect of ozagrel, a thromboxane A2 synthase inhibitor, in hyperhomocysteinemia-induced experimental vascular cognitive impairment and dementia

The present study investigates the effect of ozagrel, a selective thromboxane A2 (TXA2) inhibitor, in rat model of hyperhomocysteinemia (HHcy)-induced vascular cognitive impairment and dementia (VCID). Wistar rats were administered L-methionine (1.7 g/kg/day; p.o. × 8 weeks) to induce VCID. Morris water maze (MWM) test was employed to assess learning and memory. Endothelial dysfunction was assessed in the isolated aorta by observing endothelial-dependent vasorelaxation and levels of serum nitrite. Various biochemical and histopathological estimations were also performed. L-methionine produced significant impairment in endothelium-dependent vasorelaxation and decreases serum nitrite levels indicating endothelial dysfunction. Further, these animals performed poorly on MWM, depicting impairment of learning and memory. Further, a significant rise in brain oxidative stress level (indicated by increase in brain thiobarbituric acid-reactive species and decrease in reduced glutathione levels), brain acetylcholinesterase activity, brain myeloperoxidase activity, brain TNF-α and IL-6 levels, and brain leukocyte (neutrophil) infiltration was also observed. Treatment of ozagrel (10 and 20 mg/kg, p. o.)/donepezil (0.5 mg/kg, i.p., serving as standard) ameliorated L-methionine-induced endothelial dysfunction, memory deficits, and biochemical and histopathological changes. It may be concluded that ozagrel markedly improved endothelial dysfunction, learning and memory, and biochemical and histopathological alteration associated with L-methionine-induced VCID and that TXA2 can be considered as an important therapeutic target for the management of VCID.

Tadalafil ameliorates memory deficits, oxidative stress, endothelial dysfunction and neuropathological changes in rat model of hyperhomocysteinemia induced vascular dementia

AIM

The present study investigates the potential of Tadalafil, a phosphodiesterase-5 inhibitor, in a rat model of hyperhomocysteinemia induced vascular dementia.

METHODS

Hyperhomocysteinemia induced vascular dementia in Wistar rats was produced by administering l-Methionine (1.7 g/kg/day; p.o.×8 weeks). Learning and memory was assessed by employing Morris water maze (MWM) test. Endothelial dysfunction was assessed through acetylcholine-induced endothelial-dependent vasorelaxation and serum nitrite levels. Various other biochemical and histopathological estimations were also performed.

RESULTS

l-Methionine produced significant impairment in acetylcholine-induced endothelium-dependent vasorelaxation and a decrease in serum nitrite levels indicating endothelial dysfunction. Further, these animals performed poorly on Morris water maze, depicting impairment of learning and memory. There was a significant rise in brain oxidative stress level (indicated by an increase in brain thiobarbituric acid reactive species and a decrease in reduced glutathione levels). Increase in brain acetylcholinesterase activity; brain myeloperoxidase activity and brain neutrophil infiltration (a marker of inflammation) were also observed. Tadalafil (5 and 10 mg/kg, p.o.)/Donepezil (0.5 mg/kg, i.p., serving as standard) treatment ameliorated l-Methionine induced endothelial dysfunction; memory deficits; biochemical and histopathological changes in a significant manner.

CONCLUSIONS

It may be concluded that tadalafil has shown efficacy in the rat model of l-Methionine induced vascular dementia and that phosphodiesterase-5 can be considered as an important therapeutic target for the treatment of vascular dementia.

The Effects of Homocysteine Level in the Critically Ill Patient. A Review

Increased levels of homocysteine (HCYS) represent a risk factor for a series of physiopathological conditions: mental retardation, cardiovascular and neurodegenerative diseases, Parkinson's and Alzheimer's disease, depression, osteoporosis, endothelial dysfunction and inhibition of cell proliferation. This paper aims to present the pathophysiological implications of HCYS and the correlation of hyperhomocysteinemia (H-HCYS) with critical condition in the intensive care unit (ICU). Hypovitaminosis B and folate deficiency is directly involved in the inhibition of HCYS metabolism and the accumulation of HCYS in the plasma and tissues. Critically ill patients are more prone to H-HCYS due to hypermetabolism and accelerated synthesis produced by reactive oxygen species (ROS). In conclusion it can be affirmed that the determination and monitoring of HCYS plasma levels may be of interest in optimizing the therapy for critically ill patients. Moreover, by controlling HCYS levels, and implicitly the essential cofactors that intervene in the specific biochemical pathways, such as vitamin B6, vitamin B12 and folic acid can provide a diversified and personalized treatment for each patient.