Stabilizing proteins to prevent conformational changes required for amyloid fibril formation.

Amyloid fibrillation is associated with several human maladies, such as Alzheimer's, Parkinson's, Huntington's diseases, prions, amyotrophic lateral sclerosis, and type 2 diabetes diseases. Gaining insights into the mechanism of amyloid fibril formation and exploring novel approaches to fibrillation inhibition are crucial for preventing amyloid diseases. Here, we hypothesized that ligands capable of stabilizing the native state of query proteins might prevent protein unfolding, which, in turn, may reduce the propensity of proteins to form amyloid fibrils. We demonstrated the efficient inhibition of amyloid formation of the human serum albumin (HSA) (up to 85%) and human insulin (up to 80%) by a nonsteroidal anti-inflammatory drug, ibuprofen (IBFN). IBFN significantly increases the conformational stability of both HSA and insulin, as confirmed by differential scanning calorimetry (DSC). Moreover, increasing concentration of IBFN boosts its amyloid inhibitory propensity in a linear fashion by influencing the nucleation phase as assayed by thioflavin T fluorescence, transmission electron microscopy, and dynamic light scattering. Furthermore, circular dichroism analysis supported the DSC results, showing that IBFN binds to the native state of proteins and almost completely prevents their tendency to lose secondary and tertiary structures. Cell toxicity assay confirms that species formed in the presence of IBFN are less toxic to neuronal cells (SH-SY5Y). These results demonstrate the feasibility of using a small molecule to stabilize the native state of proteins, thereby preventing the amyloidogenic conformational changes, which appear to be the common link in several human amyloid diseases.

Ascorbic acid inhibits human insulin aggregation and protects against amyloid induced cytotoxicity.

Protein aggregation into oligomers and fibrils are associated with many human pathophysiologies. Compounds that modulate protein aggregation and interact with preformed fibrils and convert them to less toxic species, expect to serve as promising drug candidates and aid to the drug development efforts against aggregation diseases. In present study, the kinetics of amyloid fibril formation by human insulin (HI) and the anti-amyloidogenic activity of ascorbic acid (AA) were investigated by employing various spectroscopic, imaging and computational approaches. We demonstrate that ascorbic acid significantly inhibits the fibrillation of HI in a dose-dependent manner. Interestingly ascorbic acid destabilise the preformed amyloid fibrils and protects human neuroblastoma cell line (SH- SY5Y) against amyloid induced cytotoxicity. The present data signifies the role of ascorbic acid that can serve as potential molecule in preventing human insulin aggregation and associated pathophysiologies.

Diagnosis and management of uterine fibroids: current trends and future strategies.

Uterine fibroids (UFs), leiomyomas or myomas, are a type of malignancy that affects the smooth muscle of the uterus, and it is most commonly detected in women of reproductive age. Uterine fibroids are benign monoclonal growths that emerge from uterine smooth muscle cells (myometrium) as well as fibroblasts. Uterine fibroid symptoms include abnormal menstrual bleeding leading to anaemia, tiredness, chronic vaginal discharge, and pain during periods. Other symptoms include protrusion of the abdomen, pain during intercourse, dysfunctions of bladder/bowel leading to urinary incontinence/retention, pain, and constipation. It is also associated with reproductive issues like impaired fertility, conceiving complications, and adverse obstetric outcomes. It is the leading cause of gynaecological hospitalisation in the American subcontinent and a common reason for the hysterectomy. Twenty-five percent of the reproductive women experience the symptoms of uterine fibroids, and among them, around 25% require hospitalization due to the severity of the disease. The frequency of the disease remains underestimated as many women stay asymptomatic and symptoms appear gradually; therefore, the condition remains undiagnosed. The exact frequency of uterine fibroids varies depending on the diagnosis, and the population investigated; nonetheless, the incidence of uterine fibroids in reproductive women ranges from 5.4 percent to 77 percent. The uterine fibroid treatment included painkillers, supplementation with iron, vitamin D3, birth control, hormone therapy, gonadotropin-releasing hormone (GnRH) agonists, drugs modulating the estrogen receptors, and surgical removal of the fibroids. However, more research needed at the level of gene to get a keen insight and treat the disease efficiently.

Both beta sheet breaker and alpha helix forming pentapeptide inhibits protein fibrillation: Implication for the treatment of amyloid disorders.

For the first time, the effect of two novel designed pentapeptides on amyloid growth of human insulin using combined biophysical, microscopic, cell viability and computational approaches. Collective experimental data from ThT, ANS, and TEM demonstrate that in spite of having contrasting features, both peptides can effectively inhibit amyloid formation by prolonging lag phase, slowing down aggregation rate, and reducing final fibril formation (up to 84.26% and 85.24% by P1 and P7 respectively). Although pure amyloid caused profound cellular toxicity in SH-SY5Y neuronal cells, amyloid formed in the presence of peptides showed much reduced cellular toxicity. Such an inhibitory effect can be attributed to interference with the structural transition of insulin toward ß-sheet structure by peptides. Furthermore, molecular dynamic simulations confirm that peptide preferentially binds to nearby region which is more prone to form aggregates that consequently disrupts self-assembly into amyloid fibrils (P1 and P7 possess inhibition constant value of 0.000183 and 0.000216 nm, respectively), supporting our experimental observations. This study underscores the information about the sequence based inhibition mechanism of peptides that might dictate their inhibition or modulation capacity, which might be helpful in designing anti-amyloid therapeutics.

Current Pharmacological Trends on Myricetin.

Myricetin is a member of the group of flavonoids called flavonols. Myricetin is obtained from various fruit, vegetables, tea, berries and red wine. Myricetin is characterized by the pysrogallol B-ring, and the more hydroxylated structure is known to be capable for its increased biological properties compared with other flavonols. Myricetin is produced by the Myricaceae, Anacardiaceae, Polygonaceae, Pinaceae and Primulacea families. It is soluble in organic solvent such as ethanol, DMSO (dimethyl sulfoxide), and dimethyl formamide (DMF). It is sparingly soluble in aqueous buffers. Myricetin shows its various pharmacological activities including antioxidant, anti-amyloidogenic, antibacterial, antiviral, antidiabetic, anticancer, anti-inflammatory, anti-epileptic and anti-ulcer. This review article focuses on pharmacological effects of Myricetin on different diseases such as osteoporotic disorder, anti-inflammatory disorder, alzheimer's disease, anti-epileptic, cancer, cardiac disorder, diabetic metabolic disorder, hepatoprotective disorder and gastro protective disorder.

Synergistic Effect of Diallyl Sulfide With Zinc Oxide Nanorods: A Novel and Effective Approach for Treatment of Acute Dermatitis in Model Animals.

Besides inciting persistent and recurrent nosocomial afflictions, Staphylococcus aureus (S. aureus), a biofilm forming pathogen, poses an increased risk of several skin as well as respiratory tract infections as well. Emerging antimicrobial resistance trend asks to search for an alternate non-antibiotic based option to combat S. aureus pathogen. In the present study, we evaluated synergistic antimicrobial potential of Zinc oxide nanorods (ZnO-NRs) and diallyl sulphide (DAS) emulsion against methicillin resistant Staphylococcus aureus (MRSA). The antimicrobial assessment study suggests that the ZnO-NR and DAS emulsion effectively suppressed both sensitive S. aureus as well as MRSA isolates. The combination treatment showed enhanced activity even at a lower concentration as compared to the single treatment based on ZnO-NRs and DAS emulsion alone. The ZnO-NRs-DAS combination showed significant inhibition of MRSA biofilm as well. The data suggest that a combination therapy, comprising of ZnO-NRs and DAS emulsion, successfully treated experimental dermatitis infection caused by MRSA in mice model.

Elucidating the Inhibitory Potential of Designed Peptides Against Amyloid Fibrillation and Amyloid Associated Cytotoxicity.

Inhibition of fibrillation process and disaggregation of mature fibrils using small peptide are the promising remedial strategies to combat neurodegenerative diseases. However, designing peptide-based drugs to target ß-sheet-rich amyloid has been a major challenge. The current work describes, for the first time, the amyloid inhibitory potential of the two short peptides (selected on the basis of predisposition of their amino acid residues toward ß-sheet formation) using combination of biophysical, imaging methods, and docking approaches. Results showed that peptides employed different mechanisms to inhibit the amyloid fibrillation. Furthermore, they were also effective in blocking the amyloid fibrillation pathway. In contrary to the insulin fibrillar mesh, significantly less fibrillar species appeared in the presence of peptides, as confirmed by transmission electron microscopy. Circular dichroism analysis indicated that although peptides did not stabilize the native state of insulin, they inhibited amyloid aggregation by reducing the formation of ß-sheet rich structures. Hemolytic assay revealed the non-hemolytic nature of the species formed when insulin was co-incubated with the peptides. Therefore, despite the inherent potential to form ß-sheet structure, these peptides inhibited the amyloid formation and potentially can be used as therapeutics for the treatment of amyloid-related diseases.

Biophysical insight reveals tannic acid as amyloid inducer and conformation transformer from amorphous to amyloid aggregates in Concanavalin A (ConA).

The aggregation phenomenon (amyloid and amorphous) is associated with several pathological complications in human, such as Alzheimer's, Parkinson's, Huntington, Cataract diseases, and Diabetes mellitus type 2. In the present study we are offering evidence and breaking the general belief with regard to the polyphenols action as protein aggregate inhibitors. Herein we confirm that tannic acid (TA) is not only an amyloid inducer, but also it switches one type of conformation, ultimately morphology, into another. We ascertain based on our findings that aggregates are not rigid structures and the stability can be challenged under certain conditions. This study also confirms that unfolded and amorphous aggregates can serve as precursors of amyloids and TA interactions with unordered aggregates (amorphous) bringing orderliness in the conformation via amyloidosis. The shifting of unordered conformation toward orderliness is governed by the modulation in surface hydrophobic patches in Concanavalin A (ConA). Hence, a degree of exposed hydrophobic cluster can be claimed as a strong parameter to detect and distinguish the native, amorphous and both types of amyloids. Turbidity and Rayleigh light scattering measurements followed similar pattern while Thioflavin T and 1-anilino-8-naphthalene sulfonate fluorescence assays of the binding with amorphous and amyloid followed an inverse relation. Electron microscopic studies revealed the morphological variation in the ConA at 65°C as amorphous while the ConA treated with TA followed by heat treatment at 65°C was defined as amyloid in nature. Interestingly for the first time we are reporting the slight agglutination activity by the ConA amyloids.

Cationic surfactant mediated fibrillogenesis in bovine liver catalase: a biophysical approach.

Protein aggregation into oligomers and mature fibrils are associated with more than 20 diseases in humans. The interactions between cationic surfactants dodecyltrimethylammonium bromide (DTAB) and tetradecyltrimethylammonium bromide (TTAB) with varying alkyl chain lengths and bovine liver catalase (BLC) were examined by various biophysical approaches. The delicate coordination of electrostatic and hydrophobic interactions with protein, play imperative role in aggregation. In this article, we have reconnoitered the relation between charge, hydrophobicity and cationic surfactants DTAB and TTAB on BLC at pH 7.4 and 9.4 which are two and four units above pI, respectively. We have used techniques like turbidity, Rayleigh light scattering, far-UV CD, ThT, ANS, Congo red binding assay, DLS, and transmission electron microscopy. The low concentration ranges of DTAB (0-600 µM) and TTAB (0-250 µM) were observed to increase aggregation at pH 9.4. Nevertheless, at pH 7.4 only TTAB was capable of inducing aggregate. DTAB did not produce any significant change in secondary structure at pH 7.4 suggestive of the role of respective charges on surfactants and protein according to the pI and alkyl chain length. The morphology of aggregates was further determined by TEM, which proved the existence of a fibrillar structure. The surfactants interaction with BLC was primarily electrostatic as examined by ITC. Our work demystifies the critical role of charge as well as hydrophobicity in amyloid formation.

Nanoparticle-Based Mycosis Vaccine.

Many diseases that were considered major affliction of mankind in the past have been successfully eradicated with introduction of appropriate vaccine strategies. In order to expedite new challenges coming up to deal with various infectious diseases, nano-particulate-based subunit vaccines seem to be the demand of ordeal. The nano-vaccines can find better scope for the diseases that were not rampant in the semi-advanced world few years back. For example in present-day circumstances that corroborate with advancement in the field of medical sciences in terms of cancer chemotherapy, organ transplantation, therapy of autoimmune diseases, etc.; along with prevalence of altogether unheard diseases such as HIV infection, people are at risk of infliction with many more pathogens. In this regard, development of an effective prophylactic strategy against many opportunistic infections primarily caused by fungal pathogens needs better understanding of host pathogen relation and role of active immunity against pathogenic fungi. In the present study, we have tried to decipher effectiveness of a nano-sized vaccine delivery system in imparting protection against fungal pathogens.

Role of Pro-Inflammatory Cytokines and Biochemical Markers in the Pathogenesis of Type 1 Diabetes: Correlation with Age and Glycemic Condition in Diabetic Human Subjects.

BACKGROUND: Type 1 diabetes mellitus is a chronic inflammatory disease involving insulin producing ß-cells destroyed by the conjoined action of auto reactive T-cells, inflammatory cytokines and monocytic cells. The aim of this study was to elucidate the status of pro-inflammatory cytokines and biochemical markers and possible correlation of these factors towards outcome of the disease. METHODS: The study was carried out on 29 T1D subjects and 20 healthy subjects. Plasma levels of oxidative stress markers, enzymatic and non-enzymatic antioxidants were estimated employing biochemical assays. The levels of pro-inflammatory cytokines such as by IL-1ß & IL-17 in the serum were determined by ELISA, while the expression of TNF-α, IL-23 & IFN-γ was ascertained by qRT-PCR. RESULTS: The onset of T1D disease was accompanied with elevation in levels of Plasma malondialdehyde, protein carbonyl content and nitric oxide while plasma vitamin C, reduced glutathione and erythrocyte sulfhydryl groups were found to be significantly decreased in T1D patients as compared to healthy control subjects. Activity of antioxidant enzymes, superoxide dismutase, catalase, glutathione reductase and glutathione-s-transferase showed a significant suppression in the erythrocytes of T1D patients as compared to healthy subjects. Nevertheless, the levels of pro-inflammatory cytokines IL-1ß and IL-17A were significantly augmented (***p≤.001) on one hand, while expression of T cell based cytokines IFN-γ, TNF-α and IL-23 was also up-regulated (*p≤.05) as compared to healthy human subjects. CONCLUSION: The level of pro-inflammatory cytokines and specific biochemical markers in the serum of the patient can be exploited as potential markers for type 1 diabetes pathogenesis. The study suggests that level of inflammatory markers is up-regulated in T1D patients in an age dependent manner.

Vitamin k3 inhibits protein aggregation: Implication in the treatment of amyloid diseases.

Protein misfolding and aggregation have been associated with several human diseases such as Alzheimer's, Parkinson's and familial amyloid polyneuropathy etc. In this study, anti-fibrillation activity of vitamin k3 and its effect on the kinetics of amyloid formation of hen egg white lysozyme (HEWL) and Aß-42 peptide were investigated. Here, in combination with Thioflavin T (ThT) fluorescence assay, circular dichroism (CD), transmission electron microscopy and cell cytotoxicity assay, we demonstrated that vitamin k3 significantly inhibits fibril formation as well as the inhibitory effect is dose dependent manner. Our experimental studies inferred that vitamin k3 exert its neuro protective effect against amyloid induced cytotoxicity through concerted pathway, modifying the aggregation formation towards formation of nontoxic aggregates. Molecular docking demonstrated that vitamin k3 mediated inhibition of HEWL and Aß-42 fibrillogenesis may be initiated by interacting with proteolytic resistant and aggregation prone regions respectively. This work would provide an insight into the mechanism of protein aggregation inhibition by vitamin k3; pave the way for discovery of other small molecules that may exert similar effect against amyloid formation and its associated neurodegenerative diseases.

Aroylpropionic acid based 2,5-disubstituted-1,3,4-oxadiazoles: synthesis and their anti-inflammatory and analgesic activities.

Synthesis and biological evaluation of various aroylpropionic acid derivatives containing 1,3,4-Oxadiazole nucleus is reported here. The compounds (3a-w) were synthesized by cyclization of 3-aroylpropionic acids into 1,3,4-oxadiazole nucleus by treating with various aryl acid hydrazides in the presence of POCl(3). The structures of new compounds are supported by IR, (1)H NMR and MS data. These compounds were tested in vivo for their anti-inflammatory activity. All the compounds tested showed anti-inflammatory activity. The compounds which showed activity comparable to the standard drug ibuprofen were screened for their analgesic, ulcerogenic and lipid peroxidation activities. Seven (3c, g, i, j, m, o, p) out of 23 new compounds showed very good anti-inflammatory activity in the carrageenan-induced rat paw edema test with very less ulcerogenic action. The compounds, which showed less ulcerogenic action, also showed reduced malondialdehyde production (MDA), which is one of the byproducts of lipid peroxidation. Compound 3i and o showed 89.50 and 88.88% of inhibition in paw edema, 69.80 and 66.25% protection against acetic acid induced writhings and 0.7 and 0.65 of severity index respectively, compared to 90.12, 72.50 and 1.95 values of ibuprofen. The study showed that the cyclization of carboxylic group of aroylpropionic acids into an oxadiazole nucleus resulted in compounds having good anti-inflammatory and analgesic effects with reduced gastric irritation.

Fenbufen based 3-[5-(substituted aryl)-1,3,4-oxadiazol-2-yl]-1-(biphenyl-4-yl)propan-1-ones as safer antiinflammatory and analgesic agents.

The synthesis of a series of 3-[5-(substituted aryl)-1,3,4-oxadiazol-2-yl]-1-(biphenyl-4-yl)propan-1-ones derived from 4-oxo-4-(biphenyl-4-yl)butanoic acid (fenbufen) is described. The structures of these compounds were supported by IR, (1)H NMR, mass spectrometric data and elemental analysis. These compounds were tested for their antiinflammatory, analgesic, ulcerogenic and lipid peroxidation actions. A few compounds were found to have very good antiinflammatory activity in carrageenan induced rat paw edema test, while a fair number of compounds showed significant analgesic activity in acetic acid induced writhing test. The newly synthesized compounds showed very low ulcerogenic action with reduced malondialdehyde (MDA) content, which is one of the byproducts of lipid peroxidation. In vitro COX-1 and COX-2 isozyme inhibition studies were also performed on some of the selected compounds. Compound 4i and 4h were found to be more selective towards COX-2 as indicated by COX-2 selectivity index of 36.06 and 29.05 (COX-2 IC(50)=1.5 microM and 1.8 microM) respectively.