Screening of IL-22 first and second introns and FOXP3 second exon for SNPs and mutations with potential role in the susceptibility of SLE in selected population

OBJECTIVE

The main objective of performing this study was the mutational analysis of Forkhead box family member (FoxP3) and Interleukin-22 (IL-22) genes and their associations with systemic lupus erythematosus (SLE).

MATERIALS AND METHODS

A total of sixty blood samples were collected from SLE patients from different hospitals in Lahore. Proforma was based on American College of Rheumatology (ACR) criteria. The total time for this research was one year (2018-2019). DNA was extracted, and FoxP3 and IL-22 genes were polymerized through PCR and further sequenced through the Sanger Sequencing method. Chromas version 2.6.6 was used for the similarity index of sequences. NG_060763 and NG_007392.1 were used as Reference Sequences of IL-22 and FoxP3 genes, respectively.

RESULTS

Three already identified Single Nucleotide Polymorphisms (SNPs) in the IL-22 gene i.e., rs2227491, rs2227485, and rs2227513, were confirmed in the sequencing results of SLE patients. Results showed that there were nine novel mutations (27.27%) in the case of the IL-22 gene in the studied genotyped samples. These SNPs had remarkably increased allele T frequency in rs2227485 and allele C frequency in rs2227491 and rs2227513. On the other hand, in the case of FoxP3 gene exon 2, there was an addition of T at position 10 in the intronic portion, thus not involved in the progression of the disease.

CONCLUSIONS

The importance of cytokine-mediated signaling pathways, such as the IL-22 gene, is thus established. Novel variants in the IL-22 gene likely contributed significantly to the development of this autoimmune disorder. The current study found that the dysregulation of the inflammatory markers in SLE is not related to the FoxP3 gene, even though FoxP3 is implicated in the tolerance process.

Deletions of SMNI gene exon 7 and NAIP gene exon 5 in spinal muscular atrophy patients in selected population

OBJECTIVE

Spinal muscular atrophy (SMA) is common among various populations because the genetic makeup is monogamous due to consanguineous marriages. Two genes, i.e., survival motor neuron (SMN1) and neuronal apoptosis inhibitory protein (NAIP) are mapped to the SMA vicinity of chromosome 5q13. The main objective of the study was to develop a solitary advanced genetic tool for the diagnosis of SMA by using SMN1 gene exon 7 and NAIP gene exon 5.

PATIENTS AND METHODS

This study involved SMA patients (n=84) belonging to different clinical features and socio-economic status. The identity of the intact NAIP gene is primarily based on the amplification of exon 5 only in those SMA patients that have a deletion of SMN1 gene exon 7. Healthy controls (n=84) were also included in this study. The mutational analysis was observed through the Sanger sequencing method, where chromatograms were observed by using Chromas version 2.6.0.

RESULTS

This study showed a higher prevalence of SMA in females than in males. NAIP gene is considered a phenotype modifier as most SMA patients (94.90%) have SMN1 exon 7 deletion along with a deletion in exon 5 of the NAIP gene. Single nucleotide conversion C-T in exon 7 of SMN1 gene leads to its complete deletion. Mutated proteins encoded by SMN1 and NAIP genes also result in degeneration and muscle weakness in SMA patients.

CONCLUSIONS

These SMA-associated gene deletions can be used as a molecular evaluation tool for pre- and postnatal diagnosis of SMA. This will be valuable when there is a need for precise and consistent results with a strong focus on quantification.

p53 Rather Than β-Catenin Mediated the Combined Hypoglycemic Effect of Cinnamomum cassia (L.) and Zingiber officinale Roscoe in the Streptozotocin-Induced Diabetic Model

Background: The antioxidant, hypoglycemic, and insulin-enhancing effects of ginger and cinnamon were previously confirmed in experimental and human studies, while the combined effect of ginger and cinnamon was not thoroughly investigated until now.

Objectives: This study was designed to assess the antidiabetic effect of combined administration of ginger (Zingiber officinale Roscoe) and cinnamon (Cinnamomum cassia L.) in streptozotocin (STZ)-induced diabetic rats compared to metformin and to explain the mechanism behind this effect.

Materials and methods: STZ was utilized to induce diabetes mellitus in male Sprague–Dawley rats. Assessments of fasting blood glucose level (BGL), the total antioxidant capacity (TAC), serum insulin, HOMA-IR, and HOMA–β cells were performed. Pancreatic gene expression of β-catenin and p53 was assessed using RT-PCR. Assessment of histopathological alterations of pancreatic islet cells was performed using routine and immunohistochemical techniques.

Results: BGL significantly decreased (p = 0.01), while serum insulin and TAC significantly increased (p < 0.001) in both metformin- and ginger plus cinnamon–treated groups compared to the untreated diabetic group. HOMA–β cell index significantly increased (p = 0.001) in ginger plus cinnamon, indicating their enhancing effect on insulin secretion in diabetic conditions. p53 gene expression was significantly upregulated (p < 0.001), while β-catenin was insignificantly downregulated (p = 0.32) in ginger plus cinnamon–treated groups. Insulin immunoexpression in β cells significantly increased (p = 0.001, p = 0.004) in metformin- and ginger plus cinnamon–treated groups, respectively.

Conclusions: The combined administration of ginger and cinnamon has a significant hypoglycemic and antioxidant effect in STZ-induced diabetes mostly through enhancing repair of islet cells mediated via upregulation of pancreatic p53 expression. Therefore, testing this effect in diabetic patients is recommended.