Molecular docking analysis of AGTR1 antagonists

Cardiovascular diseases (CVDs) are the leading cause of death and morbidity globally. The renin-angiotensin system is an important regulatory system for maintaining cardiovascular and renal function. Therefore, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers have emerged as first-line treatments for conditions such as hypertension and heart failure. Currently available synthetic medications used to treat various CVDs have been linked with various adverse effects. Therefore, this study focuses on targeting type-1 angiotensin II receptor (AGTR1) by natural compounds. The ZINC database natural compounds and standard AGTR1 inhibitors have been screened against the AGTR1 active site. The results showed that five compounds, namely ZINC85625504, ZINC62001623, ZINC70666587, ZINC06624086, and ZINC95486187, had similar binding energies to established AGTR1 inhibitors. These compounds were found to interact with crucial AGTR1 residues, indicating their potential as AGTR1 inhibitors. Moreover, the hit compounds demonstrated favorable drug-like characteristics and warrant further investigation for their potential use in managing CVD.

Case report: A novel de novo loss of function variant in the DNA-binding domain of TBX2 causes severe osteochondrodysplasia

Background: T-box family members are transcription factors characterized by highly conserved residues corresponding to the DNA-binding domain known as the T-box. TBX2 has been implicated in several developmental processes, such as coordinating cell fate, patterning, and morphogenesis of a wide range of tissues and organs, including lungs, limbs, heart, kidneys, craniofacial structures, and mammary glands. Methods: In the present study, we have clinically and genetically characterized a proband showing a severe form of chondrodysplasia with developmental delay. Whole-exome sequencing (WES), Sanger sequencing, and 3D protein modeling were performed in the present investigation. Results: Whole-exome sequencing revealed a novel nonsense variant (c.529A>T; p.Lys177*; NM_005994.4) in TBX2. 3D-TBX2 protein modeling revealed a substantial reduction of the mutated protein, which might lead to a loss of function (LOF) or nonsense-mediated decay (NMD). Conclusion: This study has not only expanded the mutation spectrum in the gene TBX2 but also facilitated the diagnosis and genetic counseling of related features in affected families.

Development and Validation of an Arabic Version of the Drug Abuse Screening Test-10 (DAST-10) among Saudi Drug Abusers

The Drug Abuse Screening Test-10 (DAST-10) is a valid and reliable screening tool for drug use-related problems, however there is no Arabic version. To our knowledge, this is the first study to develop and validate an Arabic DAST-10 version. Saudi young adults participated in the study as two groups; drug users (n=360) recruited from Alamal Complex for Mental Health, Jeddah, and drug non-users (n=100). Three measures were used: (1) Demographic and drug use description questionnaire, (2) Arabic DAST-10 version, and (3) Urine analysis for drug use. The developed Arabic DAST-10 version demonstrated adequate internal consistency. High correlations were shown between its scores and the two standard measures (urine analysis and self-reporting question) indicating good criterion validity. Sensitivity and specificity values were between 91.5 - 99.7% and 57 - 92.5% with different DAST-10 cutoff values. An optimal performance at a cutoff score of 3 or more was most likely to significantly identify drug users. Discriminant analysis showed that more than 90% of cases were correctly classified. Distribution of participants in categories of DAST-10 scores according to degree of problems was reasonable. It is concluded that the developed Arabic DAST-10 version is a reliable and valid screening tool for drug use-related problems in Arabic speakers.

Isolation and drug susceptibility pattern of uropathogens in Saudi diabetic and non-diabetic patients with urinary tract infection

Urinary tract infection (UTI), contribute substantially to healthcare burden. Diabetes predispose to UTI with high glycosuria being fertile medium for bacterial growth. With changing bacterial drug resistance patterns; the problem needs to be studied periodically to ensure a rational therapy, minimize adverse effects, and cost. Therefore, it is of interest to compare the profile and susceptibility pattern of uropathogens isolated from diabetic and non-diabetic patients with UTI. Mid-stream urine samples of 1100 patients (diabetic and non-diabetic), presenting with UTI symptoms were aseptically collected and inoculated into CLED medium. Colony counts of 105cfu/ml or 104cfu/ml and >5 pus cells per high power microscopic field were regarded as significant bacteriuria. Colonies from CLED were sub-cultured onto sheep blood agar and MacConkey agar. Bacterial identification was performed on the basis of colony morphology, gram staining, and series of biochemical tests though Analytical Profile Index (API) test strips. Drug susceptibility was done by standard Kirby-Bauer disk diffusion. Data was analyzed by SPSS ver. 25.Clinically significant bacteriuria was 32.8% and 19.2% in diabetics and non-diabetics respectively. The frequency of male and female patients was 153 and 208 in diabetic group; and 69 and 142 respectively in non-diabetic group. Diabetics were twice at risk of UTI; [Odds ratio; 2.04 (CI: 1.68-2.48, p<0.05)]. .Escherichia coli and klebsiella were most common gram-negative, while Staphylococcus aureus and Coagulase-negative staphylococci (CoNS) were most common gram-positive bacteria in both the groups. Most effective antibiotics against gram-negative bacteria were carbapenems, amikacin, colistin, and piperacillin/tazobactam; while ampicillin/amoxicillin, fluoroquinolones and cephalexin were least effective. For gram-positives, vancomycin, linezolid and tigecycline were most effective. No significant difference in bacterial profile and susceptibility pattern was found between diabetics and non-diabetics. However, diabetics were twice at risk of UTI compared to non-diabetics.

Interactions of selected cardiovascular active natural compounds with CXCR4 and CXCR7 receptors: a molecular docking, molecular dynamics, and pharmacokinetic/toxicity prediction study

BACKGROUND

The chemokine CXCL12 and its two receptors (CXCR4 and CXCR7) are involved in inflammation and hematopoietic cell trafficking. This study was designed to investigate molecular docking interactions of four popular cardiovascular-active natural compounds; curcumin, resveratrol, quercetin, and eucalyptol; with these receptors and to predict their drug-like properties. We hypothesize that these compounds can modify CXCL12/CXCR4/CXCR7 pathway offering benefits for coronary artery disease patients.

METHODS

Docking analyses were carried and characterized by Molecular Environment (MOE) software. Protein Data Bank ( http://www.rcsb.org/ ) has been retrieved from protein structure generation and crystal structures of CXCR4 and CXCR7 receptors (PDB code = 3ODU and 6K3F). The active sites of these receptors were evaluated and extracted from full protein and molecular docking protocol was done for compounds against them. The presented parameters included docking scores, ligand binding efficiency, and hydrogen bonding. The pharmacokinetic/toxic properties (ADME/T) were calculated using SwissADME, ProTox-II, and Pred-hERG softwares to predict drug-like properties of the compounds. The thermochemical and molecular orbital analysis, and molecular dynamics simulations were also done.

RESULTS

All compounds showed efficient interactions with the CXCR4 and CXCR7 receptors. The docking scores toward proteins 3ODU of CXCR4 and 6K3F of CXCR7 were - 7.71 and - 7.17 for curcumin, - 5.97 and - 6.03 for quercetin, - 5.68 and - 5.49 for trans-resveratrol, and - 4.88 and - 4.70 for (1 s,4 s)-eucalyptol respectively indicating that all compounds, except quercetin, have more interactions with CXCR4 than with CXCR7. The structurally and functionally important residues in the interactive sites of docked CXCR4-complex and CXCR7-complex were identified. The ADME analysis showed that the compounds have drug-like properties. Only (1 s,4 s)-Eucalyptol has potential weak cardiotoxicity. The results of thermochemical and molecular orbital analysis and molecular dynamics simulation validated outcomes of molecular docking study.

CONCLUSIONS

Curcumin showed the top binding interaction against active sites of CXCR4 and CXCR7 receptors, with the best safety profile, followed by quercetin, resveratrol, and eucalyptol. All compounds demonstrated drug-like properties. Eucalyptol has promising potential because it can be used by inhalation or skin massage. To our knowledge, this is the first attempt to find binding interactions of these natural agents with CXCR4 and CXCR7 receptors and to predict their druggability.

Correction to: Protective effect of 6-paradol in acetic acid-induced ulcerative colitis in rats

An amendment to this paper has been published and can be accessed via the original article.

Protective effect of 6-paradol in acetic acid-induced ulcerative colitis in rats

Background

Ulcerative colitis is a gut inflammatory disorder due to altered immune response to gut microbiome, with interplay of environmental and genetic factors. TNF-α activates inflammatory response through a cascade of immune responses, augmenting pro-inflammatory mediators and proteases, activating chemotaxis, and infiltration of inflammatory cells, leading to ulceration and haemorrhage through cytotoxic reactive oxygen species. 6-Paradol, a dietary component in several plants belonging to the Zingiberaceae family, has shown anti-inflammatory and antioxidant activities. Current study evaluates the effect of 6-paradol in amelioration of ulcerative colitis in rats for the first time.

Methods

6-Paradol (95% purity) was obtained from seeds of Aframomum melegueta. Rats were divided randomly into six groups (n = 8). Group one was administered normal saline; group two was treated with the vehicle only; group three, sulfasalazine 500 mg/kg; and groups four, five, and six, were given 6-paradol (50, 100, 200, respectively) mg/kg orally through gastric gavage for 7 days. Colitis was induced on 4th day by intrarectal administration of 2 ml acetic acid (3%), approximately 3 cm from anal verge. On 8th day, rats were sacrificed, and distal one-third of the colon extending proximally up to 4 cm from anal orifice was taken for biochemical and gross examination. Two centimetres of injured mucosal portion was taken for histopathological investigations. SPSS (ver.26) was used for statistical analysis.

Results

Colonic and serum glutathione (GSH) levels decreased, while colonic and serum malondialdehyde (MDA), colonic myeloperoxidase (MPO) activity, serum interleukin-6 (IL-6), serum tumour necrosis factor-α (TNF-α) levels, and colon weight to length ratio were increased significantly in the colitis untreated group compared to normal control. Treatment with 6-paradol considerably improved all these parameters, especially at a dose of 200 mg/kg (p < 0.001), revealing non-significant differences with sulfasalazine 500 mg/kg and normal control (p = 0.998). Sulfasalazine and 6-paradol in a dose dependent manner also markedly reversed mucosal oedema, atrophy and inflammation, cryptic damage, haemorrhage, and ulceration. There were non-significant differences between low and medium doses and between medium and high doses of 6-paradol for IL-6 and serum MDA levels.

Conclusion

6-Paradol demonstrated protection against acetic acid-induced ulcerative colitis, probably by anti-inflammatory and antioxidant actions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03203-7.

Effect of genetic polymorphisms in SREBF-SCAP pathway on therapeutic response to rosuvastatin in Saudi metabolic syndrome patients

AIM

Genetic variants contribute to statins' therapeutic variability. SREBF-SCAP pathway is a key player in lipid homeostasis. Hence, effect of SREBF-SCAP polymorphisms on therapeutic response was studied.

PATIENTS & METHODS

Metabolic syndrome patients of either sex were prescribed rosuvastatin 10 mg for 24 weeks. Clinical, anthropometric and lipid measurements were done before and after treatment. Genotyping was done by pyrosequencing.

RESULTS & CONCLUSION

No associations of SCAP and SREBF-1a genotypes with baseline lipids but significant associations with lipid reductions were observed. Significant effect of SCAP (GG; B = -8.16, p = 0.001); SREBF-1a (GG; B = -7.47, p = 0.001) and SREBF-1a (-delG; B = -7.42, p = 0.001) was observed on total cholesterol reduction. Additive trend was found between SCAP genotypes and lipid reductions. A total of 88% responders have SCAP 'G' allele (p = 0.001). Patients carrying SCAP (GG) and SREBF-1a (GG and -delG) have 9.5-, 8.6- and 14.6-times more likelihood of being responders (p < 0.05). 'G' allele in SCAP and SREBF-1a is significant predictor of rosuvastatin response.

Cystic fibrosis: current therapeutic targets and future approaches

Objectives

Study of currently approved drugs and exploration of future clinical development pipeline therapeutics for cystic fibrosis, and possible limitations in their use.

Methods

Extensive literature search using individual and a combination of key words related to cystic fibrosis therapeutics.

Key findings

Cystic fibrosis is an autosomal recessive disorder due to mutations in CFTR gene leading to abnormality of chloride channels in mucus and sweat producing cells. Respiratory system and GIT are primarily involved but eventually multiple organs are affected leading to life threatening complications. Management requires drug therapy, extensive physiotherapy and nutritional support. Previously, the focus was on symptomatic improvement and complication prevention but recently the protein rectifiers are being studied which are claimed to correct underlying structural and functional abnormalities. Some improvement is observed by the corrector drugs. Other promising approaches are gene therapy, targeting of cellular interactomes, and newer drugs for symptomatic improvement.

Conclusions

The treatment has a long way to go as most of the existing therapeutics is for older children. Other limiting factors include mutation class, genetic profile, drug interactions, adverse effects, and cost. Novel approaches like gene transfer/gene editing, disease modeling and search for alternative targets are warranted.

Effect of sequential versus standard Helicobacter pylori eradication therapy on the associated iron deficiency anemia in children

Objectives:

Helicobacter pylori infection may be associated with low iron stores and iron deficiency anemia. Eradication of infection by the standard 10-day therapy (a proton pump inhibitor [PPI], clarithromycin and amoxicillin; each given orally, twice daily) is decreasing. The sequential 10-day therapy (a PPI and amoxicillin; each given orally twice daily for 5 days; followed by a PPI, clarithromycin and tinidazole; each given orally twice daily for another 5 days) may achieve higher eradication rates. This study was designed to investigate, which eradication regimen; sequential or standard; more effectively improves the associated iron status and iron deficiency in children.

Materials and Methods:

Children (12-15 years) with H. pylori active infection (positive H. pylori immunoglobulin G and urea breath test [UBT]) were subjected to measurement of serum ferritin and then randomized into two groups to receive standard and sequential eradication therapy. Six weeks after completing therapy, UBT was performed to check eradication and serum ferritin was measured to estimate affection by therapy. Statistical Package for Social Sciences (SPSS, IBM, NY, USA) was used for analysis.

Results:

H. pylori eradication rates of sequential versus standard therapy were non-significantly different. Serum ferritin non-significantly differed between the two therapy groups and in the same group before and after treatment.

Conclusions:

There is no significant difference in H. pylori eradication rates between sequential and standard therapies in children. Moreover, no significant relationship was found between eradication therapy and serum ferritin. Further studies enrolling more markers of iron deficiency are required to precisely assess this relationship.