Macrophage memories of early-life injury drive neonatal nociceptive priming

The developing peripheral nervous and immune systems are functionally distinct from those of adults. These systems are vulnerable to early-life injury, which influences outcomes related to nociception following subsequent injury later in life (i.e., "neonatal nociceptive priming"). The underpinnings of this phenomenon are unclear, although previous work indicates that macrophages are trained by inflammation and injury. Our findings show that macrophages are both necessary and partially sufficient to drive neonatal nociceptive priming, possibly due to a long-lasting remodeling in chromatin structure. The p75 neurotrophic factor receptor is an important effector in regulating neonatal nociceptive priming through modulation of the inflammatory profile of rodent and human macrophages. This "pain memory" is long lasting in females and can be transferred to a naive host to alter sex-specific pain-related behaviors. This study reveals a mechanism by which acute, neonatal post-surgical pain drives a peripheral immune-related predisposition to persistent pain following a subsequent injury.

Plant biomarkers as early detection tools in stress management in food crops: a review

MAIN CONCLUSION

Plant Biomarkers are objective indicators of a plant's cellular state in response to abiotic and biotic stress factors. They can be explored in crop breeding and engineering to produce stress-tolerant crop species. Global food production safely and sustainably remains a top priority to feed the ever-growing human population, expected to reach 10 billion by 2050. However, abiotic and biotic stress factors negatively impact food production systems, causing between 70 and 100% reduction in crop yield. Understanding the plant stress responses is critical for developing novel crops that can adapt better to various adverse environmental conditions. Using plant biomarkers as measurable indicators of a plant's cellular response to external stimuli could serve as early warning signals to detect stresses before severe damage occurs. Plant biomarkers have received considerable attention in the last decade as pre-stress indicators for various economically important food crops. This review discusses some biomarkers associated with abiotic and biotic stress conditions and highlights their importance in developing stress-resilient crops. In addition, we highlighted some factors influencing the expression of biomarkers in crop plants under stress. The information presented in this review would educate plant researchers, breeders, and agronomists on the significance of plant biomarkers in stress biology research, which is essential for improving plant growth and yield toward sustainable food production.

Macrophage epigenetic memories of early life injury drive neonatal nociceptive priming

The developing peripheral nervous and immune systems are functionally distinct from adults. These systems are vulnerable to early life injury, which influences outcomes related to nociception following subsequent injury later in life (neonatal nociceptive priming). The underpinnings of this phenomenon are largely unknown, although previous work indicates that macrophages are epigenetically trained by inflammation and injury. We found that macrophages are both necessary and partially sufficient to drive neonatal nociceptive priming possibly due to a long-lasting epigenetic remodeling. The p75 neurotrophic factor receptor (NTR) was an important effector in regulating neonatal nociceptive priming through modulation of the inflammatory profile of rodent and human macrophages. This pain memory was long lasting in females and could be transferred to a naive host to alter sex-specific pain-related behaviors. This study reveals a novel mechanism by which acute, neonatal post-surgical pain drives a peripheral immune-related predisposition to persistent pain following a subsequent injury.

Attenuating effects of Azanza garckeana fractions on glycemo-impaired-associated dyslipidemia, hepatopathy, and nephropathy

OBJECTIVES

The use of medicinal plants for diabetes treatment is increasing owing to their effectiveness and safety compared to synthetic drugs. Thus, the ameliorative effects of Azanza garckeana (F. Hoffm.) fractions in diabetes-induced dyslipidemia, hepatopathy, and nephropathy in rats were evaluated in this study.

METHODS

Rats with alloxan (120 mg/kg body weight (BW))-induced diabetes were randomized into different groups (n=5) and treated with the crude methanolic extract, and fractions (n-hexane, ethyl acetate, and aqueous fractions) of A. garckeana each at 100, 200, and 400 mg/kg BW. Glibenclamide (5 mg/kg BW) was used as a reference drug, and all treatments were administered orally daily for 6 weeks.

RESULTS

Our data revealed that treatment with the crude extract caused a dose-dependent hypoglycemic effect of 61.32±3.45%, 76.05±3.05%, and 78.59±5.90% at 100, 200, and 400 mg/kg BW, respectively and improved the BW of the animals. The extract also ameliorated the elevated cholesterol, triglyceride, low-density lipoprotein cholesterol, and increased serum levels of high-density lipoprotein cholesterol compared with untreated control animals. The extract also reversed serum biochemical alterations in aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, creatinine, total and direct bilirubin, urea, and uric acid that were observed in untreated diabetic rats. Interestingly, the A. garckeana fraction also exhibited significant protection against diabetes-induced dyslipidemia, hepatopathy, and nephropathy in rats, with the ethyl acetate fraction exhibiting a remarkable protective effect. The LC-MS characterisation of the active fraction identified the presence of various phenolic and flavonoid compounds that could be responsible for the bioactivity of the fraction.

CONCLUSION

Collectively, this study suggests the potential application of A. garckeana for effective treatment of diabetic nephropathy, with the ethyl acetate fraction of this plant representing a reserve of potential candidates for developing new drugs.

Synthesis, substitution kinetics, DNA/BSA binding and cytotoxicity of tridentate N^E^N (E = NH, O, S) pyrazolyl palladium(II) complexes

The pincer complexes, [Pd(L₁)Cl]BF₄ (PdL₁), [Pd(L₂)Cl]BF₄ (PdL₂), [Pd(L₃)Cl]BF₄ (PdL₃), [Pd(L₄)Cl]BF₄ (PdL₄) were prepared by reacting the corresponding ligands, 2,6-bis[(1H-pyrazol-1-yl)methyl]pyridine (L₁), bis[2-(1H-pyrazol-1-yl)ethyl]amine (L₂), bis[2-(1H-pyrazol-1-yl)ethyl]ether (L₃), and bis[2-(1H-prazol-1-yl)ethyl]sulphide (L₄) with [PdCl₂(NCMe)]₂ in the presence NaBF₄. The solid-state structures of complexes PdL₁-PdL₄ confirmed a tridentate coordination mode, with one chloro ligand completing the coordination sphere to afford square-planar complexes. Chemical behaviour of the complexes in solution confirms their stability in both aqueous and DMSO stock media. The electrochemical properties of the compounds showed irreversible two-electron reduction process. Kinetic reactivity of Pd complexes with the biological nucleophiles viz, thiourea (Tu), L-methionine (L-Met) and guanosine 5'-diphosphate disodium salt (5'-GMP) followed the order: PdL₂ < PdL₃ < PdL₄, and PdL₂ < PdL₁. The kinetic reactivity is subject to the electronic effects of the spectator ligand(s), and the trend was supported by the DFT computed results. The palladium complexes PdL₁-PdL₄ bind to calf thymus (CT-DNA) via intercalation mode. In addition, the bovine serum albumin (BSA) showed good binding affinity to the complexes. The mode of quenching mechanism of the intrinsic fluorescence of CT-DNA and BSA by the complexes was found to be static. The order of interactions of the complexes with DNA and BSA was in tandem with the rate of substitution kinetics. The complexes, however, displayed relatively low cytotoxicity (IC₅₀ > 100 µM) when tested against the human cervical adenocarcinoma (HeLa) cell line and the transformed human lung fibroblast cell line (MRC-5 SV2).

Nanotechnology-Based Strategies for Effective and Rapid Detection of SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic has gained worldwide attention and has prompted the development of innovative diagnostics, therapeutics, and vaccines to mitigate the pandemic. Diagnostic methods based on reverse transcriptase-polymerase chain reaction (RT-PCR) technology are the gold standard in the fight against COVID-19. However, this test might not be easily accessible in low-resource settings for the early detection and diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The lack of access to well-equipped clinical laboratories, requirement for the high level of technical competence, and the cost of the RT-PCR test are the major limitations. Moreover, RT-PCR is unsuitable for application at the point-of-care testing (PoCT) as it is time-consuming and lab-based. Due to emerging mutations of the virus and the burden it has placed on the health care systems, there is a growing urgency to develop sensitive, selective, and rapid diagnostic devices for COVID-19. Nanotechnology has emerged as a versatile technology in the production of reliable diagnostic tools for various diseases and offers new opportunities for the development of COVID-19 diagnostic systems. This review summarizes some of the nano-enabled diagnostic systems that were explored for the detection of SARS-CoV-2. It highlights how the unique physicochemical properties of nanoparticles were exploited in the development of novel colorimetric assays and biosensors for COVID-19 at the PoCT. The potential to improve the efficiency of the current assays, as well as the challenges associated with the development of these innovative diagnostic tools, are also discussed.

Advances in Nanotechnology towards Development of Silver Nanoparticle-Based Wound-Healing Agents

Since antiquity, silver-based therapies have been used in wound healing, wound care and management of infections to provide adequate healing. These therapies are associated with certain limitations, such as toxicity, skin discolouration and bacterial resistance, which have limited their use. As a result, new and innovative wound therapies, or strategies to improve the existing therapies, are sought after. Silver nanoparticles (AgNPs) have shown the potential to circumvent the limitations associated with conventional silver-based therapies as described above. AgNPs are effective against a broad spectrum of microorganisms and are less toxic, effective at lower concentrations and produce no skin discolouration. Furthermore, AgNPs can be decorated or coupled with other healing-promoting materials to provide optimum healing. This review details the history and impact of silver-based therapies leading up to AgNPs and AgNP-based nanoformulations in wound healing. It also highlights the properties of AgNPs that aid in wound healing and that make them superior to conventional silver-based wound treatment therapies.

Synthesis, computational and biological studies of alkyltin(IV) N-methyl-N-hydroxyethyl dithiocarbamate complexes

Methyltin(IV) of butyltin(IV)-N-hydroxyethyl dithiocarbamate complexes, represented as [(CH3)2Sn(L(OH))2] and [(C4H9)2Sn(L(OH))2] respectively were synthesized and characterized using spectroscopic techniques (1H, 13C and 119Sn NMR) and elemental analysis. Both infrared and NMR data showed that, the complexes were formed via two sulphur atoms of the dithiocarbamate group. This mode of coordination was further supported by the DFT calculation, which suggested the formation of a distorted octahedral geometry around the tin atom. The complexes were screened for their antioxidant, cytotoxicity and anti-inflammatory properties. Four different assays including DPPH, nitric oxide, reducing power and hydrogen peroxides were used for the antioxidant studies, while an in vitro anti-inflammatory study was done using albumin denaturation assay. The complexes showed good antioxidant activity, especially in the DPPH assay. Butyltin(IV)-N-hydroxyethyl dithiocarbamate showed better cytotoxicity activity compared to methyltin(IV)-N-hydroxyethyl dithiocarbamate in the selected cell lines, which included KMST-6, Caco-2 and A549 cell lines. The anti-inflammatory activities revealed that the two complexes have useful activities better than diclofenac used as control drug.

Role of π-conjugation on the coordination behaviour, substitution kinetics, DNA/BSA interactions, and in vitro cytotoxicity of carboxamide palladium(II) complexes

Treatments of N-(pyridin-2-ylmethyl)pyrazine-2-carboxamide (L1), N-(quinolin-8-yl)pyrazine-2-carboxamide (L2), N-(quinolin-8-yl)picolinamide (L3) and N-(quinolin-8-yl)quinoline-2-carboxamide (L4) with [PdCl2(NCMe)]2 afforded the corresponding Pd(ii) complexes, [Pd(L1)Cl] (PdL1); [Pd(L2)Cl] (PdL2); [Pd(L3)Cl] (PdL3); and [Pd(L4)Cl] (PdL4) in moderate yields. Structural characterisation of the compounds was achieved by NMR and FT-IR spectroscopies, elemental analyses and single crystal X-ray crystallography. The solid-state structures of complexes PdL2-PdL4 established the presence of one tridentate carboxamide and Cl ligands around the Pd(ii) coordination sphere, to give distorted square planar complexes. Electrochemical investigations of PdL1-PdL4 showed irreversible one-electron oxidation reactions. Kinetics reactivity of the complexes towards bio-molecules, thiourea (Tu), l-methionine (L-Met) and guanosine 5'-diphosphate disodium salt (5'-GMP) decreased in the order: PdL1 > PdL2 > PdL3 > PdL4, in tandem with the density functional theory (DFT) data. The complexes bind favourably to calf thymus (CT-DNA), and bovine serum albumin (BSA), and the order of their interactions agrees with the substitution kinetics trends. The in vitro cytotoxic activities of PdL1-PdL4 were examined in cancer cell lines A549, PC-3, HT-29, Caco-2, and HeLa, and a normal cell line, KMST-6. Overall, PdL1 and PdL3 displayed potent cytotoxic effects on A549, PC-3 HT-29 and Caco-2 comparable to cisplatin. All the investigated complexes exhibited lower toxicity on normal cells than cisplatin.

Investigation of bioactive compounds in Crassocephalum rubens leaf and in vitro anticancer activity of its biosynthesized gold nanoparticles

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GC–MS analysis of Crassocephalum rubens extracts were investigated.

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Gold nanoparticles (AuNPs) were synthesized using aqueous extract of Crassocephalum rubens (AECR).

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DPPH radical scavenging activity of AECR was similar to that of AECR-AuNPs.

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AECR-AuNPs are potential anticancer agents against MCF-7 and Caco-2 cell lines.

The development of cancer therapies has become difficult due to high metastasis, and lack of tissue selectivity, which in most cases affects normal cells. Demand for anticancer therapy is therefore increasing on daily basis. Gold nanoparticles (AuNPs) have many applications in biomedical field. Biological synthesis of AuNPs using aqueous extract of Crassocephalum rubens (AECR) was designed to investigate the in vitro anticancer potential. The synthesized AuNPs were characterized by UV–vis spectroscopy, high-resolution transmission electron microscopy, and Fourier transform infrared spectroscopy. The characterization results showed the formation of green AuNPs of wavelength 538 nm, and mostly spherical AuNPs with 20 ± 5 nm size. Significant anticancer activity of the AECR-AuNPs on MCF-7 and Caco-2 cells was noted at higher concentrations (125 and 250 μg/mL) during 24 and at all concentrations tested during 48 h. It can therefore be concluded that AECR leaves can mediate stable AuNPs with anticancer properties.

Biological synthesis of gold and silver nanoparticles using leaf extracts of Crassocephalum rubens and their comparative in vitro antioxidant activities

The use of plant and plant products in the synthesis of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) is made possible because of the natural inherent phytochemicals responsible for the reduction of respective metallic salts to nanoparticle forms, and ensuring therapeutic applicability. In this study, synthesis of AgNPs and AuNPs was performed using two different aqueous extraction methods for Crassocephalum rubens: maceration using laboratory method of extraction (cold aqueous extract of Crassocephalum rubens (AECR)), and decoction using traditional healer's method of extraction (hot aqueous crude extract of Crassocephalum rubens (CECR)). The synthesized nanoparticles were characterized using various methods, and in vitro antioxidant potential were thereafter investigated. The characterization results indicated the formation of mostly spherical-shaped AgNPs and AuNPs with surface plasmon resonance (SPR) band of 470 nm and 540 nm, respectively. The nanoparticles possess high antioxidant potentials but AECR synthesized AuNPs exhibited the least phytochemical contents and antioxidant potential when compared to other nanoparticles. It can therefore be concluded that extraction method and nanoparticle type are important factors that could influence the antioxidant properties of the nanoparticles. Further studies using these nanoparticles as anticancer or anti-inflammatory agent in both in vitro and in vivo are underway.

MicroRNA Assisted Gene Regulation in Colorectal Cancer

Colorectal cancer (CRC) is the second-leading cause of cancer death and a major public health problem. Nearly 80% CRC cases are diagnosed after the disease have metastasized and are often too advanced for treatment. Small non-coding RNA guides argonaute protein to their specific target for regulation as the sole of RNA induced silencing complex for gene silencing. These non-coding RNA for example microRNA, are thought to play a key role in affecting the efficiency of gene regulation in cancer, especially CRC. Understanding the mechanism at the molecular level could lead to improved diagnosis, treatment, and management decisions for CRC. The study aimed to predict the molecular mechanism of gene regulation based microRNA-mRNA duplex as a lead in the silencing mechanism. Five candidate microRNAs were identified through the in silico approach. The MicroRNA target prediction and subsequent correlation, and prioritization were performed using miRTarBase, gbCRC and CoReCG, and DAVID databases respectively. Protein selection and preparation were carried out using PDB and Schrödinger suits. The molecular docking analysis was performed using PATCHDOCK webserver and visualized by discovery studio visualizer. The results of the study reveal that the candidate microRNAs have strong binding affinity towards their targets suggesting a crucial factor in the silencing mechanism. Furthermore, the molecular docking of the receptor to both the microRNA and microRNA-mRNA duplex were analyzed computationally to understand their interaction at the molecular level. Conclusively, the study provides an explanation for understanding the microRNAs-based gene regulation (silencing mechanism) in CRC.

In vitro antioxidant activities and inhibitory effects of phenolic extract of Senecio biafrae (Oliv and Hiern) against key enzymes linked with type II diabetes mellitus and Alzheimer's disease

The phenolic extract of Senecio biafrae leaves was investigated to determine the in vitro antioxidant, phenolic profiles, and inhibition of key enzymes relevant to type II diabetes mellitus (α-amylase and α-glucosidase) and Alzheimer's disease (acetylcholinesterase and butrylcholinesterase). The phenolic extract demonstrated significant scavenging abilities against all in vitro antioxidant parameters assessed. Reversed-phase HPLC of the extract revealed the presence of gallic acid, chlorogenic, caffeic acid, rutin, quercetin, and kaempferol. The extract also inhibited activities of α-amylase (IC 50 = 126.90 μg/ml), α-glucosidase (IC 50 = 139.66 μg/ml), acetylcholinesterase (IC 50 = 347.22 μg/ml), and butrylcholinesterase (IC 50 = 378.79 μg/ml), which may be attributed to the antioxidant potential of the extract and its phenolic composition. Therefore, this study suggests that the leaves of S. biafrae may be useful in the management of diabetes mellitus and Alzheimer's disease.

Ameliorative Activity of Ethanol Extract of Artocarpus heterophyllus Stem Bark on Pancreatic β-Cell Dysfunction in Alloxan-Induced Diabetic Rats

This study sought to investigate the ameliorative effects of ethanol extract Artocarpus heterophyllus (EAH) in alloxan-induced diabetic rats. The rats were divided into 6 groups, with groups 1 and 2 serving as nondiabetic and diabetic control, respectively; group 3 serving as diabetic rats treated with 5 mg/kg glibenclamide; and groups 4 to 6 were diabetic rats treated with 50, 100, and 150 mg/kg of EAH, respectively. Assays determined were serum insulin, lipid peroxidation, and antioxidant enzyme activities. EAH stem bark reduced fasting blood glucose and lipid peroxidation levels and increased serum insulin levels and activities of antioxidant enzymes. Data obtained demonstrated the ability of EAH stem bark to ameliorate pancreatic β-cell dysfunction in alloxan-induced diabetic rats.

Evaluation of acute and subacute toxicity of aqueous extract of Crassocephalum rubens leaves in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Crassocephalum rubens is found throughout tropical Africa including the Indian Ocean islands. The leaves are commonly eaten in form of soups and sauces in South-Western Nigeria, also in other humid zones of Africa. Traditionally, it is used as an antidote against any form of poisoning; used to treat stomach and liver complaints; and externally to treat burns, sore eyes, earache, leprosy and breast cancer. In this study, acute and subacute toxicity of aqueous extract of C. rubens leaves was evaluated in rats in order to assess its safety profile.

MATERIALS AND METHODS

In acute toxicity study, rats were given a single oral administration of aqueous extract of C. rubens leaves at graded doses (250-5000mg/kg). The animals were monitored for behavioural changes and possible mortality over a period of 24h and thereafter, for 14 days. In the subacute toxicity study, rats of both sexes were administered C. rubens orally at doses of 250mg/kg, 500mg/kg, 750mg/kg and 1000mg/kg body weight daily, for 28 days. Rats were observed weekly for any changes in general behaviour and body weights. In addition, other relevant parameters were assayed at the end of the main and reversibility study periods.

RESULTS

There was no observed adverse effect; including mortality in the animals. The extract caused no significant difference in the body weights as well as organs weights of treated groups when compared with the control groups. Haematological and biochemical parameters also revealed no toxic effects of the extract on rats. Histological assessments were normal in liver and kidney.

CONCLUSIONS

It can therefore be suggested based on the results from this study that aqueous extract of C. rubens leaves, at dosage levels up to 1000mg/kg, is non-toxic and could also offer protection on some body tissues. Aqueous extract of C. rubens could therefore, be considered safe. This study supports the application of Crassocephalum rubens in traditional medicine.