Terapias naturales para la reducción de complicaciones en pacientes con diabetes tipo 2 y COVID-19 / Natural therapies for the reduction of complications in patients with type 2 diabetes and COVID-19

Background: In December 2019, a series of cases occurred in Wuhan (China), caused by a new coronavirus. On March 11, 2020, the WHO declared the COVID-19 disease, caused by SARS-CoV-2, as a pandemic. In Peru, the first person infected with SARS-CoV-2 was confirmed on March 6, 2020. The number of infected has been constantly increasing to this day. Purpose: It is relevant to the current pandemic, understanding the mechanism of infection of SARS-CoV-2 in diabetic patients and in this way to be able to provide natural alternatives to reduce the complications that these patients can carry out until death. Methodology: An information search was carried out between April 6 and August 25 of 2020 in databases and indexed journals, whose articles have been published between 2011 and 2020. Results: It was found regarding inhibitors of dipeptidyl peptidase (DPP-4) evaluated in in vitro tests, that the Berberis aristata species has a metabolite called "berberine", which has the highest inhibitory capacity among the mentioned species, and, concerning furine inhibition, among the in vitro tests, catechin has a significant inhibitory capacity; it also has DPP-4 inhibitory activity. Conclusion: There is a great variety of medicinal plants with inhibitory properties for DPP-4 and some for furin. These properties are beneficial in patients with type 2 diabetes, since they reduce the activity of these proteases and, consequently, the complications in SARS-CoV-2 infection

Antecedentes: En diciembre de 2019, se registraron una serie de casos producidos por un nuevo coronavirus en Wuhan (China). El 11 de marzo de 2020, la Organización Mundial de la Salud declaró a la COVID-19, provocada por el coronavirus 2 causante del síndrome respiratorio agudo grave (SARS-CoV-2), como una pandemia. En el Perú, la primera persona infectada por SARS-CoV-2 fue confirmada el 6 de marzo de 2020; desde entonces, la cifra de infectados ha ido en constante aumento hasta el día de hoy. Propósito: Es relevante, ante la actual pandemia, entender el mecanismo de infección del SARS-CoV-2 en pacientes diabéticos, para, de esta manera, poder dar alternativas naturales para disminuir las complicaciones que pueden llevar a estos pacientes hasta la muerte. Metodología: se realizó una búsqueda de información entre el 6 de abril y el 25 de agosto de 2020, en bases de datos y revistas indexadas, cuyos artículos han sido publicados entre 2011 y 2020. Resultados: Se encontró, en cuanto a los inhibidores de la dipeptidilpeptidasa 4 (DPP-4) evaluados en ensayos in vitro, que la especie Berberis aristata posee un metabolito denominado "berberina", el cual presentó la mayor capacidad inhibitoria entre las especies analizadas. Con respecto a la inhibición de la furina, en los ensayos in vitro, la catequina posee una capacidad inhibitoria significativa; además de actividad inhibitoria para la DPP-4. Conclusión: Existe una gran variedad de plantas medicinales con propiedades inhibitorias para la DPP-4, y algunas de ellas para la furina. Estas propiedades son beneficiosas en pacientes con diabetes tipo 2, dado que reducen la actividad de estas proteasas y, por consiguiente, las complicaciones causadas por la infección por SARS-CoV-2

Importance of the putative furin recognition site 742RNRR745 for antiangiogenic Sema3C activity in vitro

Angiogenesis is one of the key processes in the growth and development of tumors. Class-3 semaphorins (Sema3) are characterized as axon guidance factors involved in tumor angiogenesis by interacting with the vascular endothelial growth factor signaling pathway. Sema3 proteins convey their regulatory signals by binding to neuropilins and plexins receptors, which are located on the effector cell. These processes are regulated by furin endoproteinases that cleave RXRR motifs within the Sema, plexin-semaphorins-integrin, and C-terminal basic domains of Sema3 protein. Several studies have shown that the furin-mediated processing of the basic domain of Sema3F and Sema3A is critical for association with receptors. It is unclear, however, if this mechanism can also be applied to other Sema3 proteins, including the main subject of this study, Sema3C. To address this question, we generated a variant of the full-length human Sema3C carrying point mutation R745A at the basic domain at the hypothetical furin recognition site 742RNRR745, which would disable the processing of Sema3C at this specific location. The effects produced by this mutation were tested in an in vitro angiogenesis assay together with the wild-type Sema3C, Sema3A, and Sema3F proteins. Our results showed that the inhibitory effect of Sema3C on microcapillary formation by human umbilical vein endothelial cells could be abrogated upon mutation at the Sema3C basic domain within putative furin cleavage site 742RNRR745, indicating that this site was essential for the Sema3 biological activity.

A novel treatment for weight reduction by the recombinant "Pichia pastoris" yeast expressing the hybrid protein of "irisin-furin-transferrin" / 中西医结合学报

Obesity is a major health problem across the world, but there are few ways to effectively treat or manage it in the long term. Researchers are searching for more convenient, cost-effective and noninvasive therapies for overweight and obese people. Recent studies have illustrated that the microbiome of the body's different organs can be used as a vehicle for in-situ gene therapy. We suggest that the recombinant form of "Pichia pastoris" yeast expressing the hybrid protein of "irisin-furin-transferrin" under the control of the enolase 1 promoter is a new nutraceutical strategy to absorb fewer calories from intestinal nutrients, and induce a higher metabolic rate to expend more calories, similar to that from engaging in physical activity. By comparison, this method can be a long-term, noninvasive treatment and can be used for obese patients who have movement limitations.

Effects of α1-PDX, a furin inhibitor, on growth, invasion, and tumorigenicity of cervical cancer HeLa cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of the furin inhibitor α1-PDX on the growth, invasion, and tumorigenicity of cervical cancer cells and explore the mechanisms.</p><p><b>METHODS</b>The changes in the growth, migration and invasion of α1-PDX-transfected HeLa cells were observed using MTT assay, Boyden migration and invasion assay. The protein levels of furin and MT1-MMP were measured using Western blotting and furin activity was detected by enzyme activity assay in the transfected cells. HeLa cells were seeded subcutaneously in nude mice and the tumor volume changes were recorded.</p><p><b>RESULTS</b>Compared with the control cells, α1-PDX-treated cells showed a significant growth inhibition by 18.4% at 24 h (P<0.01) with obviously lowered migration ability and cell invasiveness (P<0.01). Treatment with α1-PDX significantly reduced furin enzyme activity and MTI-MMP protein levels in HeLa cells. In nude mice, α1-PDX-treated HeLa cells exhibited a delayed and lowered tumorigenicity with reduced size of the tumors.</p><p><b>CONCLUSION</b>α1-PDX can inhibit the growth, metastasis and tumorigenicity of HeLa cells, the mechanism of which may involve a decreased furin activity and MTI-MMP expression.</p>

Relationship between genetic variation of furin gene and hypercholesterolemia and hyper-low-density lipoprotein cholesterolemia in Kazakh general population / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the relationship between the genetic variation of Furin gene and the hypercholesterolemia and hyper-low-density lipoprotein cholesterolemia in Kazakh general population.</p><p><b>METHODS</b>Based on a cross-sectional epidemiological study in a Kazakh general population, a case-control study including 878 subjects was conducted. All the sequence variant-located promoters and exon regions of Furin gene were identified by the direct sequencing of PCR products in 48 randomly selected hypercholesterolemic individuals (24 males and 24 females). After having genotyped the representative polymorphisms in 878 subjects by TaqMan PCR, we investigated the relationship between genetic variation of Furin and hypercholesterolemia/hyper-low-density lipoprotein cholesterolemia in these subjects.</p><p><b>RESULTS</b>Twelve genetic variations in Furin gene were identified by sequencing 48 hypercholesterolemic individuals and 4 common single nucleotide polymorphisms (rs6226, rs6227, rs2071410, and rs4932178)were selected as the representatives for genotyping in these subjects. The rs6226, rs6227, rs2071410, and rs4932178 polymorphisms were successfully genotyped. The distribution of the genotypes, alleles, and haplotypes of rs6226, rs6227, rs2071410, and rs4932178 polymorphisms did not differ significantly between the hypercholesterolemia group and the control groups or between the hyper-low-density lipoprotein cholesterolemia group and the control groups (all P>0.05). The cholesterol and low-density lipoprotein cholesterol levels did not differ significantly among individuals with different genotypes (all P>0.05).</p><p><b>CONCLUSION</b>The genetic variation of Furin may not be associated with hypercholesterolemia or hyper-low-density lipoprotein cholesterolemia in Kazakh general population.</p>

Association between sequence variation of Furin gene and obesity in ethnic Kazakh from Xinjiang / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association between sequence variation of Furin gene and obesity in ethnic Kazakh population in Xinjiang region.</p><p><b>METHODS</b>Based on a cross-sectional epidemiological study, a case-control study was conducted. All sequence variants located promoter and exon regions of Furin gene were identified with direct sequencing of PCR products from 66 randomly chosen obese individuals (33 males and 33 females). Polymorphisms representative of a general ethnic Kazakh population (856 subjects, including 364 males and 492 females, 478 from obesity group and 378 from control group) were determined by TaqMan PCR, the association between sequence variation of Furin gene and obesity was assessed.</p><p><b>RESULTS</b>Twelve sequence variations in Furin gene were identified through sequencing of 66 obese individuals. And 4 common SNPs (rs6226, rs6227, rs2071410 and rs4932178) were selected as representative polymorphisms for the general Kazakh population. Above polymorphisms were successfully typed in all subjects. Distribution of the genotypes, alleles, and haplotypes formed by such polymorphisms did not differ significantly between the case and control groups or males and females (P>0.05). The waist circumference also did not differ significantly among individuals with different genotypes (P>0.05).</p><p><b>CONCLUSION</b>Genetic variations of Furin gene are not associated with obesity in Kazakh general population.</p>

Hepatitis B virus-mediated effects on host expression of the proprotein convertase Furin / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the effects of hepatitis B virus (HBV) infection on the expression of Furin, an important proprotein convertase, in liver cells to provide insights towards its potential as a therapeutic target for improved antiviral efficacy.</p><p><b>METHODS</b>Furin expression was measured in human liver specimens (infected tissues from patients with chronic HBV hepatitis vs. normal tissues from healthy donors) and in hepatoma cell lines (HBV-infected HepG2.2.15 cells vs. uninfected parental cell lines HepG2) using quantitative real-time RT-PCR (for mRNA), western blotting and immunohistochemistry (for protein).</p><p><b>RESULTS</b>Compared to the uninfected tissues and cells, the HBV-infected tissue and cells showed down-regulated expression of furin at both the mRNA and protein levels. In particular, the HepG2.2.15 cells showed -50% less furin mRNA expression than the HepG2 cells and the difference was statistically significant (P less than 0.05).</p><p><b>CONCLUSION</b>HBV may suppress the host cell's expression of furin, possibly to benefit its survival and replication in the host cell.</p>

Relationship between genetic variation of furin and insulin resistance in Chinese Kazakh population / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between genetic variation of Furin and insulin resistance in Chinese Kazakh population.</p><p><b>METHODS</b>Based on a cross-sectional epidemiological study in a Chinese Kazakh population, a case-control study was conducted. All the sequence variants located promoter and exon regions of Furin were identified by directly sequencing of PCR product in 50 (25 males) individuals with insulin resistance, which were randomly chosen from the study population. The representative polymorphism was detected by TaqMan PCR in 861 subjects (366 males, 254 in case group and 607 in control group). The relationship between genetic variation of Furin and insulin resistance in this cohort was analyzed.</p><p><b>RESULTS</b>Twelve genetic variations in Furin were identified by sequencing 50 individuals with insulin resistance and 4 common SNPs (rs6226, rs6227, rs2071410, and rs4932178) were selected as representatives for genotyping in this Chinese Kazakh population. The rs6226, rs6227, rs2071410, and rs4932178 polymorphisms were successfully genotyped. The distribution of the genotypes of rs6226, rs6227, rs2071410, and rs4932178 polymorphism was similar between case and controls (all P > 0.05). The homeostasis model assessment for insulin resistance (HOMA-IR) levels was also similar among individuals with different genotypes (all P > 0.05).</p><p><b>CONCLUSION</b>The genetic variation of Furin is not associated with insulin resistance in this cohort of Chinese Kazakh population.</p>

Study on a putative, proprotein convertase-cleaved product of HBV core protein in vitro / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the cleavage of HBV core protein in vivo by proprotein convertase furin or its family members and observe the intracellular localization of the putative cleaved product.</p><p><b>METHODS</b>Recombinant HBV core protein was incubated with furin under different conditions in vitro, and the reaction was checked with Western blotting. The recombinant vectors expressed the putative cleaved fragment and intact core protein (serves as control) were constructed. The stable expression cell lines were established by transfecting constructs into HepG2 cell line, for which indirect immunofluorescence staining was used by monoclonal anti-HBc against the region shared by core protein and its cleaved product .The confocal microscopy was carried out to observe the intracellular distribution.</p><p><b>RESULTS</b>HBV core protein was cleaved by furin in vitro under different tested conditions. The molecular weight of the major cleaved product just about 15,000 was in concordance with the expectation. The expressed cleaved fragment could react to the monoclonal antibody against core protein, and mainly located in cytosol in particle style just like the intact core protein.</p><p><b>CONCLUSION</b>HBV core protein can be cleaved by furin in vitro. The major cleaved product has similar antigenicity and subcellular distribution to core protein. These data suggest that proprotein convertase furin or its family members play important roles in HBV replication regulation, and the cleaved product may be involved in antiviral immunity of HBV infection. Further investigations are imperative.</p>

Cloning of Novel Epidermal Growth Factor (EGF) Plasmid for Gene Therapy on Diabetic Foot Ulcer / 당뇨병

BACKGROUND: Epidermal Growth Factor (EGF) is one of the important growth factors involved in the epithelialization during cutaneous wound healing. Peptide EGF has been used for the treatment of diabetic foot ulcer. But the inferiority of cost-effectiveness and the inconvenience of daily application might have restricted its wide clinical usage. EGF gene therapy could dramatically improve the efficacy and inconvenience through long-term expression and bypassing the EGF degradation by hostile non-specific proteinases expressed in the wound bed. METHODS: EGF DNAs were amplified via PCR. For the more effective secretion from the transfected cell, we inserted furin cleavage site into EGF plasmids. The efficacy of novel plasmid pbeta-EGF was verified by transfection into the various animal cell lines, and the biologic potency of expressed EGF was confirmed via phosphorylation of PI3K and GSK3beta by Western blotting. RESULTS: We tested various kinds of human EGFs. One of the human EGF isoforms, EGF(828) including a membrane-anchoring domain was successfully released as the mature EGF protein in the cell culture media. Also EGF plasmid including furin cleavage site showed more than 2-fold increased EGF expression compared with the sequence without furin cleavage site. CONCLUSION: In conclusion, these findings suggest that mature EGF could be released easily out of cells by modifying EGF DNA sequence. Our novel EGF plasmid DNA could markedly increase the efficiency of non-viral gene therapy for diabetic foot ulcer.