SnO2-xNx based tpod nanostructure for SARS-CoV2 spike protein detection

The worldwide spreading of severe acute respiratory syndrome SARS-CoV2 pandemic, a massive setback to every human being. In response to strategies actions against Covid-19 spreading many detection, prevention, and post-measures are being studied in large capacities. Association of SARS-CoV2 with ACE2 is well acknowledged and used for developing point-of-care detection kits. Recently, cases and studies have surfaced showing relation of ACE I/D polymorphism with spreading of SARS-CoV2 and highlighted a slip section towards detection and these studies show specificity with older males, high diabetes, and hypertension. To address the raised concern, we report synthesis of unique SnO2-xNx tpod nanostructure, showing affirmative attachment to both ACE1 and ACE2 efficiently. The attachment is examined in different ratios and studied with μ-Raman spectroscopy. The tpod nanostructure has served with its signature raman signals and used as probe for detection of SARS-CoV2 spike protein (S1). The linearity response for tpod raman signal at 630.4 cm-1 shows R2 0.9705, comparatively peak 1219.13 cm-1 show R2 0.9865 and calculated limit of detection of 35 nM.

Association of ACE Gene Insertion/Deletion Polymorphism with Suicidal Attempt in an Iranian Population

Deregulation of the renin-angiotensin system (RAS) plays an important role in suicide. Angiotensin converting enzyme (ACE) gene is a key component in this system. The relationship between insertion/deletion (I/D) polymorphism of ACE gene with suicide attempt (SA) is controversial. According to previous studies, allele D in this polymorphism has been considered as a potential risk factor for suicide. However, no study has been conducted in Iran to investigate this matter. This case-control study has focused on investigating the association of ACE I/D polymorphism (rs1799752) with SA in an Iranian population. The frequency of genotypes was 14% for II, 55% for ID, and 31% for DD in the case group (100 persons), and 18% for II, 74% for ID, and 8% for DD in control group (100 persons). Results show there was a significant difference in the distribution of ACE I/D polymorphism genotypes in men with SA compared to controls, as well as in women with SA compared to controls. Also, there was a significant association between DD genotype and the risk of SA compared to II genotype as reference. The severity of depression was significantly different between DD and II genotypes in SA group. According to the results, we suggest that the presence of DD genotype is possibly associated with an increased risk of SA. Maybe part of that is related to severity of depression in DD genotypes carriers of ACE I/D polymorphism.

Advances in Structural Biology of ACE and Development of Domain Selective ACE-inhibitors

BACKGROUND

The Angiotensin-I converting enzyme (ACE) is one of the most important components of the renin-angiotensin-aldosterone system controlling blood pressure and renal functions. Inhibitors of ACE are first line therapeutics used in the treatment of hypertension and related cardiovascular diseases. Somatic ACE consists of two homologous catalytic domains, the C- and N-domains. Recent findings have shown that although both domains are highly homologous in structure, they may have different physiological functions. The C-domain is primarily involved in the control of blood pressure, in contrast to the N-domain that is engaged in the regulation of hematopoietic stem cell proliferation. The currently available ACE inhibitors have some adverse effects that can be attributed to the non-selective inhibition of both domains. In addition, specific Ndomain inhibitors have emerged as potential antifibrotic drugs. Therefore, ACE is still an important drug target for the development of novel domain-selective drugs not only for the cardiovascular system but also for other systems.

OBJECTIVE

Detailed structural information about interactions in the protein-ligand complex is crucial for rational drug design. This review highlights the structural information available from crystallographic data which is essential for the development of domain selective inhibitors of ACE.

METHODS

Over eighty crystal complexes of ACE are placed into the Protein Database. An overview of X-ray ACE complexes with various inhibitors in C- and N-domains and an analysis of their binding mode have given mechanistic explanation of the structural determinants of selective ligand binding. In addition, ACE domain selective inhibitors with dual modes of action in complexes with ACE are also discussed.

CONCLUSION

Selectivity of ACE inhibitors for the N- and C-domain is controlled by subtle differences in the amino-acids forming the active site. Reported studies of crystal complexes of inhibitors in the C- and N-domains revealed that most selective inhibitors interact with non-conserved amino-acids between domains and have distinct interactions with the residues in the S2 and S2' subsites of the ACE catalytic site. Moreover, unusual binding of the second molecule of inhibitors in the binding cavity opens new possibilities of exploiting more distant regions of the catalytic center in structure-based design of novel drugs.

In vitro effect of oxidized and reduced glutathione peptides on angiotensin converting enzyme purified from human plasma

Angiotensin converting enzyme (ACE, peptidyldipeptidase A, EC 3.4.15.1) plays an important role in the regulation of blood pressure. In this study, ACE was purified from human plasma by affinity chromatography in single step. The enzyme purified in 5367-fold from human plasma and specific activity was found to be 1208 EU/mg protein. The purity and molecular weight of ACE were determined by SDS-PAGE, which indicated two bands at around 60 kDa and 70 kDa on the gel. Effect of oxidized glutathione (GSSG) peptide and reduced glutathione (GSH) peptide on purified ACE activity were also investigated in which lisinopril was used as reference inhibitor. GSSG showed activation effect on ACE activity whereas GSH provided inhibition effect. In the lights of activity (%) versus activator graph for GSSG and activity (%) versus inhibitor graphs for GSH and lisinopril; IC₅₀ values for GSH and lisinopril were determined to be 16.2 μM and 0.781 nM, respectively. Type of inhibition for GSH and lisinopril from graph Lineweaver-Burk was found to be reversible non-competitive inhibition and K_i constants for GSH and lisinopril were calculated as 11.7 μM and 0.662 nM, respectively.

DNA methylation and genetic variation of the angiotensin converting enzyme (ACE) in depression

BACKGROUND

Depression is one of the most prevalent psychiatric disorders, and in older persons is associated with high levels of comorbidity and under-treatment. Dysfunction of the hypothalamic-pituitary-adrenal (HPA) stress axis is consistently observed in the older population as well as depressed patients, with the angiotensin converting enzyme (ACE) a key regulator of the stress response. Epigenetic regulation of ACE may play an important role in HPA axis (dys)regulation.

OBJECTIVE

To investigate ACE promoter methylation as a biomarker of late-life depression, and its association with genetic variation and cortisol secretion.

METHOD

The longitudinal general population ESPRIT study is aimed at investigating psychiatric disorders in older persons (n=1863, average age=73). Depression was assessed using the Mini International Neuropsychiatric Interview according to DSM-IV criteria and the Centre for Epidemiologic Studies Depression Scale (CES-D). Genotype information for seven polymorphisms across the ACE gene was also available. Blood and saliva samples collected at baseline and used to extract DNA and measure cortisol, respectively. Sequenom MassARRAY was used to measure promoter DNA methylation of the ACE gene (n=552).

RESULTS

There was no evidence of an association between ACE promoter methylation and depression. However, there was evidence that ACE genetic variants influenced methylation, and modified the association between depression and methylation (Δ at various sites; -2.05% to 1.74%; p=0.019 to 0.039). Multivariate analyses were adjusted for participants' lifestyle, health and medical history. Independent of depression status, ACE methylation was inversely correlated with cortisol levels (r=-0.336, p=0.042).

CONCLUSION

This study provides evidence that associations between ACE methylation and depression are genotype-dependent, suggesting that the development of reliable depression biomarkers may need to consider methylation levels in combination with underlying genetic variation. ACE methylation may also be a suitable biomarker of cortisol and/or HPA axis activity.

Disease marker combination enhances patient characterization in the Finnish sarcoidosis patients

Sarcoidosis is an inflammatory disease of unknown etiology and multiple clinical phenotypes. Clinical manifestations range from asymptomatic disease to severe loss-of-function leading to the hypothesis that sarcoidosis might not be just one disease, but consists of several distinct disease entities each with potentially distinct genetic associations. We have previously demonstrated that in our series HLADRB1* 03:01 and haplotype HLA-DRB1*04:01-DPB1*04:01 are associated with good prognosis sarcoidosis. In our recent work, we found a novel SNP (rs9905945) in the 5'upstream region of the ACE gene to be associated with favorable disease prognosis as well. The main objective of this study was to expand the previous results and analyse combined influence of the found ACE SNP rs9905945 with the protective HLA markers HLADRB1* 03:01 and HLA-DRB1*04:01-DPB1*04:01 in 188 Finnish sarcoidosis patients (resolved disease, n = 90; persistent disease, n = 98). When combining the frequencies of the rs9905945 and of the HLA markers, the strongest association was found for a combination of either/or both HLA markers and rs9905945 for good disease prognosis (37.1% in resolved vs. 11.3% in persistent, p < 0.001, OR = 4.61, (95%CI 2.15-9.86)). In conclusion, we discovered that a combination of the ACE SNP rs9905945 and HLA markers enhance the accuracy for predicting disease course in Finnish sarcoidosis patients further characterizing genetic differences between Finnish sarcoidosis patients with different prognosis.

The angiotensin converting enzyme (ACE) inhibitor, captopril disrupts the motility activation of sperm from the silkworm, Bombyx mori

Angiotensin I-converting enzyme (also known as peptidyl dicarboxypeptidase A, ACE, and EC 3.4.15.1), which is found in a wide range of organisms, cleaves C-terminal dipeptides from relatively short oligopeptides. Mammalian ACE plays an important role in the regulation of blood pressure. However, the precise physiological functions of insect ACE homologs have not been understood. As part of our effort to elucidate new physiological roles of insect ACE, we herein report a soluble ACE protein in male reproductive secretions from the silkmoth, Bombyx mori. Seminal vesicle sperm are quiescent in vitro, but vigorous motility is activated by treatment with either a glandula (g.) prostatica homogenate or trypsin in vitro. When seminal vesicle sperm were pre-incubated with captopril, a strong and specific inhibitor of mammalian ACE, and then stimulated to initiate motility by the addition of the g. prostatica homogenate or trypsin, the overall level of acquired motility was reduced in an inhibitor-concentration-dependent manner. In the course of this project, we detected ACE-related carboxypeptidase activity that was inhibited by captopril in both the vesicular (v.) seminalis of the noncopulative male reproductive tract and in the spermatophore that forms in the female bursa copulatrix at the time of mating, just as in an earlier report on the tomato moth, Lacanobia oleracea, which belongs to a different lepidopteran species (Ekbote et al., 2003a). Two distinct genes encoding ACE-like proteins were identified by analysis of B. mori cDNA, and were named BmAcer and BmAcer2, respectively [the former was previously reported by Quan et al. (2001) and the latter was first isolated in this paper]. RT-qPCR and Western blot analyses indicated that the BmAcer2 was predominantly produced in v. seminalis and transferred to the spermatophore during copulation, while the BmAcer was not detected in the adult male reproductive organs. A recombinant protein of BmAcer2 (devoid of a signal peptide) that was expressed in Escherichia coli cells exhibited captopril-sensitive carboxypeptidase activities. Our findings show that the BmAcre2 gene encodes a secreted ACE protein included in the Bombyx seminal plasma. In particular, the silkworm ACE protein in the seminal fluid might be involved in the signaling pathway that leads to the activation and regulation of sperm motility.

Cardiovascular effect of inflammation and nonsteroidal anti-inflammatory drugs on renin-angiotensin system in experimental arthritis

A co-morbidity of inflammatory conditions is increased cardio-renal risks. Additionally, nonsteroidal anti-inflammatory drugs (NSAIDs) which are used to treat pain and inflammation are also associated with increase in such risks. We hypothesized that inflammation and NSAIDs impose the cardio-renal risk through the activation of the renin-angiotensin-system (RAS), a regulating pathway of the renal and cardiovascular homeostasis. We investigated the effect of adjuvant arthritis and NSAIDs on the RAS. Western blotting and ELISA were used to measure the RAS components. Inflammation caused significant imbalances in the cardiac and renal angiotensin converting enzymes, their biologically active angiotensin peptides (AngII and Ang1-7) and the target proteins involved in the peptide-receptor binding (AngII type 1 and type 2, and Ang1-7 receptor, Mas) toward cardio-renal toxicity. However, 7 days treatment of arthritic animals with NSAIDs (rofecoxib, meloxicam, celecoxib and flurbiprofen) restored the constitutive balances, perhaps due to their anti-inflammatory properties. Inflammation exerts its cardio-renal effects by causing imbalance in the RAS. NSAIDs through their anti-inflammatory effect restore this imbalance. Thus, mechanisms other than imbalances in the RAS may be involved in the NSAIDs cardiotoxicity.

Conventional markers in determination of activity of sarcoidosis

AIM AND BACKGROUND

Currently, there are no objective criteria to determine sarcoidosis activity. The present study aimed to discover a sensitive serum marker that would determine the activity of sarcoidosis and can be used during disease follow-up.

METHODS

Forty-eight patients with sarcoidosis and twenty healthy volunteers as a control group were included in the study. On their control visits, the patients were divided into active and inactive groups based on their clinical, physiological, and radiological status. Angiotensin converting enzyme (ACE), adenosine deaminase (ADA), total IgE (T-IgE), C-reactive protein (CRP), serum amyloid-A (SAA), and soluble interleukin-2 receptor (sIL2R) serum levels and classical findings of activity were compared, and the utilization of these parameters as markers of activity was investigated.

RESULTS

Thirty-nine cases were female (female/male: 39/9) and the mean age was 44.29±10.9years. Thirty-seven cases were active and 11 cases were inactive. Serum ACE, ADA, sIL2R, and SAA levels were significantly higher while T-IgE levels were lower in the sarcoidosis cases. A comparison of the markers between active and inactive cases showed that only SAA was significantly higher (p<0.001). sIL2R was elevated in cases with extra-pulmonary involvement (p<0.014). The area under the curve value was rather high for ADA (0.98 CI: 0.96-1.0); it also had high sensitivity (93.8%) and specificity (100%), and therefore had the highest diagnostic value (96.6%).

CONCLUSION

The current study showed that SAA wil be helpfull for detecting the activity of srcoidosis, IL2R measurement in exploring the extra-pulmonary organ involvement.

Angiotensin Converting Enzyme Gene Polymorphism and its Association with Hypertension in South Indian Population

Hypertension, a well known risk factor for various cardiovascular, peripheral vascular and renal events is an important public health challenge. Renin angiotensin system (RAS) being the most vital pathogenic mechanism of hypertension is mediated by a key component; the angiotensin converting enzyme (ACE). The present study was aimed to know the relationship of ACE gene polymorphism and the possible risk of development of hypertension in south Indian population. The study included 101 clinically diagnosed hypertensive patients without any associated disease condition and 81 age and sex matched apparently healthy controls. Genotyping was performed using a polymerase chain reaction, (PCR) amplification of the intron 16 fragment harboring the 287 bp Alu repeat sequence. Three possible genotypes D/D, I/I homozygous and I/D heterozygous were analyzed where the D/D genotypes corresponds to higher ACE levels (D-Deletion, I-Insertion). The PCR products were separated on 2 % agarose gel. Statistical analysis was performed using SPSS.15 software program. We found a significance in frequency of D/D genotype in the hypertensive patients compared to the control group (p = 0.0005, odd's ratio = 4.157). This suggested that ACE (D/D) genotypes are more prone for the development of hypertension. This is relatively a pilot study; but nevertheless may assist in identifying the pathophysiological cause of hypertension.