Nanotoxicology and Nanomedicine: The Yin and Yang of Nano-Bio Interactions for the New Decade.

Nanotoxicology and nanomedicine are two sub-disciplines of nanotechnology focusing on the phenomena, mechanisms, and engineering at the nano-bio interface. For the better part of the past three decades, these two disciplines have been largely developing independently of each other. Yet recent breakthroughs in microbiome research and the current COVID-19 pandemic demonstrate that holistic approaches are crucial for solving grand challenges in global health. Here we show the Yin and Yang relationship between the two fields by highlighting their shared goals of making safer nanomaterials, improved cellular and organism models, as well as advanced methodologies. We focus on the transferable knowledge between the two fields as nanotoxicological research is moving from pristine to functional nanomaterials, while inorganic nanomaterials - the main subjects of nanotoxicology - have become an emerging source for the development of nanomedicines. We call for a close partnership between the two fields in the new decade, to harness the full potential of nanotechnology for benefiting human health and environmental safety.

Mitigating Human IAPP Amyloidogenesis In Vivo with Chiral Silica Nanoribbons.

Amyloid fibrils generally display chirality, a feature which has rarely been exploited in the development of therapeutics against amyloid diseases. This study reports, for the first time, the use of mesoscopic chiral silica nanoribbons against the in vivo amyloidogenesis of human islet amyloid polypeptide (IAPP), the peptide whose aggregation is implicated in type 2 diabetes. The thioflavin T assay and transmission electron microscopy show accelerated IAPP fibrillization through elimination of the nucleation phase and shortening of the elongation phase by the nanostructures. Coarse-grained simulations offer complementary molecular insights into the acceleration of amyloid aggregation through their nonspecific binding and directional seeding with the nanostructures. This accelerated IAPP fibrillization translates to reduced toxicity, especially for the right-handed silica nanoribbons, as revealed by cell viability, helium ion microscopy, as well as zebrafish embryo survival, developmental, and behavioral assays. This study has implicated the potential of employing chiral nanotechnologies against the mesoscopic enantioselectivity of amyloid proteins and their associated diseases.

Pharmacological screening of Monotheca buxifolia (Falc.) A. DC. for antinociceptive, anti-inflammatory and antipyretic activities.

BACKGROUND: Medicinal plants have proven their importance as a valuable source of molecules with therapeutic potential. Monotheca buxifolia (Falc.) A. DC. (family: Sapotaceae) is traditionally used as a hematinic, laxative, digestive, anthelmintic, antipyretic, and in the treatment of gastro-urinary disorders. To provide scientific evidence for its folkloric use, the present study investigated Monotheca buxifolia fruit hydro-ethanolic extract (MBHE) for its prospective antinociceptive, anti-inflammatory and antipyretic activities. MBHE was eluted through column chromatography to isolate the bioactive secondary metabolites which may probably involve in its beneficial properties. METHODS: The phytochemical constituents in MBHE was elucidated using UV, IR, (1)H-NMR, (13)C NMR, 2D-NMR spectra in combination with EIMS and FAB-MS spectrometric techniques and comparison with literature data of related compounds. The antinociceptive activity of MBHE was evaluated in the acetic acid induced abdominal constriction assay; the anti-inflammatory potential was assessed in the carrageenan induced paw edema, while the antipyretic effect was tested against brewer's yeast induced pyrexia in BALB/c mice at doses of 50, 100 and 150 mg/kg. RESULTS: Elution of MBHE along with various characterization techniques led to the isolation of oleanolic acid and isoquercetin. Significant attenuation of chemical induced nociception was observed with MBHE at tested doses of 50 mg/kg (P < 0.01, 68.87 %), 100 mg/kg (P < 0.01, 68.87 %) and 150 mg/kg (P < 0.001, 83.02 %). During a duration of 1-5 h in the carrageenan induced paw edema assay, significant ameliorative effect (P < 0.01, P < 0.001) was demonstrated by MBHE at 50 mg/kg (22.94-20 %), 100 mg/kg (33.23-21.13 %) and 150 mg/kg (38.23-25 %). MBHE also significantly alleviated the brewer's yeast induced pyrexic response when tested at doses of 50 mg/kg (P < 0.05 in 2nd h), 100 mg/kg (P < 0.05, P < 0.01 and P < 0.001 in 1-5 h) and 150 mg/kg (P < 0.01 and P < 0.001 in 1-5 h). CONCLUSION: These findings suggest that Monotheca buxifolia possess pain, inflammation and pyrexia ameliorating properties, probably mediated by the presence of oleanolic acid and isoquercetin contents, though the involvement of other important phytochemicals constituents cannot be ignored.

Lecithin-gold hybrid nanocarriers as efficient and pH selective vehicles for oral delivery of diacerein-In-vitro and in-vivo study.

We report the synthesis and evaluation of lecithin-gold hybrid nanocarriers for the oral delivery of drugs with improved pharmacokinetics, Au-drug interactive bioactivity and controlled drug releasing behavior at physiological pH inside human body. For this purpose, diacerein, a hydrophobic anti-arthritic drug, was loaded in lecithin NPs (LD NPs), which were further coated by Au NPs either by in-situ production of Au NPs on LD NPs or by employing pre-synthesized Au NPs. All LDAu NPs were found to release drug selectively at the physiological pH of 7.4 and showed 2.5 times increase in the oral bioavailability of diacerein. Pharmacological efficacy was significantly improved i.e., greater than the additive effect of diacerein and Au NPs alone. LDAu NPs started suppressing inflammation at first phase, whereas LD NPs showed activity in the second phase of inflammation. These results indicate the interaction of Au NPs with prostaglandins and histaminic mediators of first phase of carrageenan induced inflammation. Acute toxicity study showed no hepatic damage but the renal toxicity parameters were close to the upper safety limits. Toxicity parameters were dependent on surface engineering of LDAu NPs. Apart from enhancing the oral bioavailability of hydrophobic drugs and improving their anti-inflammatory activity, these hybrid nanocarriers may have potential applications in gold-based photothermal therapy and the tracing of inflammation at atherosclerotic and arthritic site.

Evaluation of anti-inflammatory, analgesic and antipyretic activities of Thymus serphyllum Linn. in mice.

The present study was conducted to evaluate the analgesic, anti-inflammatory and antipyretic activities of Thymus serphyllum Linn. in mice. Anti-inflammatory activity was evaluated by carrageenan and egg albumin induced paw edema in mice, while analgesic activity was assessed using formalin induced paw licking and acetic acid induced abdominal writhing in mice. For determination of antipyretic activity, pyrexia was induced by subcutaneous injection of 20% yeast. All the extracts produced significant anti-inflammatory effect however, ether extract produced maximum effect 34% inhibition (p < 0.001) against carrageenan and 22% (p < 0.01) inhibition against egg albumin induced paw edema in mice at the end of 3 h. Ether extract produced prominent analgesic effect 77% (p < 0.001) inhibition in acetic acid induced abdominal writhing and 59% inhibition in formalin induced paw licking model in mice, respectively. Ether extract also demonstrated significant (p < 0.001) antipyretic activity against yeast induced pyrexia. The plant showed no sign of toxicity up to the dose of 2000 mg/kg in mice. This study supports the use of Thymus serphyllum in traditional medicine for inflammation accompanied by pain and fever.

Possible mechanism of cardiac depressant activity of Berberis orthobotrys roots in isolated rabbit heart.

Berberis orhob, otrvs Bien. ex Aitch. (B.o.) has been reported to have antihypertensive effect in different experimental models. The aim of present study was to evaluate the possible antihypertensive mechanism. Aqueous methanolic extract of B.o. roots and its various fractions namely (ethyl acetate, n-butanol or aqueous) in different concentrations (10 ng/mL, 100 ng/mL, I pg/mL, 10 pg/mL, 100 pg/mL ) were evaluated in isolated perfused rabbit heart to assess their effect on force of contraction, HR and perfusion pressure. The crude extract of B.o. and its fractions exhibited a significant decrease in heart rate, contractility and perfusion pressure of isolated rabbit heart, however, butanolic fraction produced more prominent effect and was selected for further study. The effects of butanol fraction were not blocked by atropine (10' M) in isolated perfused heart. However, butanol fraction significantly blocked the effects of adrenaline (10' M). It is therefore conceivable that cardiac depressant activity of B.o. butanol fraction might be due to the presence of certain 3-blocking agents which might be responsible for antihypertensive effect However, further experiments are required to isolate the active compound(s) and elucidate exact mechanism of action.