The mixture of cashew nut shell liquid and castor oil results in an efficient larvicide against Aedes aegypti that does not alter embryo-fetal development, reproductive performance or DNA integrity

Supplementation of high doses of vitamin D during the gestational period do not cause reproductive, teratogenic and genotoxic damage in mice

Vitamin D deficiency during pregnancy may have adverse effects on embryo-fetal and postnatal development. Indeed, vitamin D supplementation has been indicated for pregnant women. However, there are no studies that indicate the safe dose of this supplementation during the gestational period. Therefore, the present study assessed the effects of high doses of vitamin D and vitamin D combined with calcium on reproductive performance, embryo-fetal development, and DNA integrity in Swiss mice. A total of 140 pregnant female mice treated with vitamin D and vitamin D combined with calcium were analyzed in two experiments. In one experiment, mice received intramuscular supplementation at doses of 600,000, 6,000,000, or 60,000,000 IU of vitamin D. These same doses were also associated with the dose of 8.56 mg/kg of calcium. In the other experiment, mice received a single oral dose of 6,000, 60,000, or 600,000 IU of vitamin D. These same doses were also associated with the dose of 8.56 mg/kg of calcium. The treatments were always carried out in the 10th gestational day. The results show that neither intramuscularly nor orally administered vitamin D and vitamin D combined with calcium affected reproductive performance, embryo-fetal development, or DNA integrity at the different doses tested. These pioneering results confirm the safety of using this type of high doses of supplementation, including during pregnancy.

Absence of maternal-fetal adverse effects of Alternanthera littoralis P. Beauv. following treatment during pregnancy in mice

Alternanthera littoralis P. Beauv is a plant native to Brazil that exhibits various beneficial activities including antioxidant, antibacterial, antifungal, antiprotozoal, anti-hyperalgesic, and anti-inflammatory properties. The aim of this study was to assess the impact of the ethanol extract of Alternanthera littoralis (EEAl) on reproductive outcomes, embryofetal development, and DNA integrity of pregnant female mice. Pregnant Swiss female mice were randomly assigned to three experimental groups (n = 10): controls were administered either 1% Tween 80 (vehicle), EEAl 100 mg/kg or EEAl 1000 mg/kg. Treatment was administered through gavage during the gestational period until day 18. On gestational days 16, 17, and 18, a peripheral blood sample from the tail vein was obtained for DNA integrity analysis (micronucleus test). After the last collection, animals were euthanized by cervical dislocation. Maternal organs and fetuses were collected, weighed, and subsequently analyzed. Reproductive outcome parameters were assessed by measurement of number of implants, live fetuses, and resorptions. Embryonic development was determined by adequacy of weight for gestational age as well as determination of external, visceral, and skeletal malformations. Data demonstrated that EEAl did not produce maternal toxicity at either dose associated with no marked alterations in any of the reproductive outcome parameters including implantation sites, live/dead fetuses ratio, fetal viability, post-implantation losses, resorptions, and resorption rate. However, EEAl 1000 group reduced embryofetal development by lowering placental weight. In addition, there was an increase in the frequency of external and skeletal malformations in the EEAl 1000 group, which could not be attributed to extract exposure as these values were within control levels. Based upon our findings, evidence indicates that the EEAl at the concentrations employed in our study may be considered safe for use during pregnancy and extracts of this plant show potential for development of phytomedicines to be used in pregnancy.

The ethanolic extract of Salvia lachnostachys Benth is not maternotoxic, does not alter reproductive performance, but has teratogenic potential

Salvia lachnostachys Benth is native to Brazil and has anti-inflammatory, anti-arthritic, cytotoxic, antitumor, and antihyperalgesic activities. The population, including pregnant women, consume this plant to treat pain, inflammation, flu, spasms, insomnia, and depression, mainly. There are no safety reports on the use of this plant during pregnancy. The present study aimed to evaluate the effects of S. lachnostachys ethanolic extract (EESl) on reproductive performance, embryofetal development, and DNA integrity of pregnant female mice. Pregnant females were randomly divided into three experimental groups (n = 10): The Control group was treated with a vehicle, and treatment groups were administered with EESl at 100 and 1000 mg/kg, respectively. Treatment occurred by gavage throughout the gestational period until day 18. Afterward, reproductive performance, embryofetal development, and DNA integrity parameters were evaluated. The results indicated that EESl did not alter any reproductive performance parameters. However, it changed embryofetal outcome through reduced placental weight (EESl 100 mg/kg), decreased fetal weight (EESl 100 and 1000 mg/kg), and increased frequency of small for gestational age fetuses (EESl 1000 mg/kg). In addition, EES1 increased the frequency of external, visceral, and skeletal malformations. Because of the above, it is considered that EESl is not maternotoxic, does not alter reproductive performance, but does alter embryofetal development. Its use in the gestational period is not indicated due to its teratogenic potential.

The Ethanolic Extract of Piper glabratum Kunth Is Teratogenic and Interferes with the Ossification Process of Swiss Mice Fetuses

Piper glabratum Kunth is a plant traditionally used to treat pain and inflammation in the Mato Grosso do Sul, Brazil. Even pregnant women consume this plant. Toxicology studies of the ethanolic extract from the leaves of P. glabratum (EEPg) could establish the safety of popular use of P. glabratrum. Thus, the effects of the ethanolic extract of leaves of P. glabratum (EEPg) on the reproductive performance and embryofetal development of Swiss mice were evaluated. Pregnant female mice were treated with 100, 1000 and 2000 mg/kg throughout the gestational period by gavage (p.o). The control group received the EEPg vehicle (Tween 80–1%) in the proportion of 0.1 mL/10 g (p.o.). The results demonstrated that EEPg has low maternal toxic potential and does not alter the reproductive performance of females. However, it altered embryofetal development and caused fetal weight reduction (increasing the frequency of small-for-gestational-age fetuses) at the two highest doses. In addition, it interfered with placental weight, placental index and placental efficiency. The frequency of visceral malformations increased by 2.8 times for the lowest dose of EEPg, and skeletal malformations increased by 2.48, 1.89 and 2.11 times for doses of 100, 1000 and 2000 mg/kg of EEPg, respectively. It is noteworthy that 100% of the offspring treated with EEPg showed changes in the ossification process. Thus, it is considered that the EEPg has low maternal toxic potential; it does not alter the reproductive performance of females. However, it is teratogenic and interferes, mainly, in the ossification process, and therefore its use is contraindicated in the gestational period.

The Ethanolic Extract of Gomphrena celosioides Mart. Does Not Alter Reproductive Performance or Embryo-Fetal Development, nor Does It Cause Chromosomal Damage

Gomphrena celosioides is a native Brazilian plant found in the State of Mato Grosso do Sul. It is used in folk medicine to treat kidney diseases, skin diseases, infections, rheumatism, gastrointestinal diseases, and respiratory diseases. It is also used as an abortifacient. To evaluate the effects of the ethanolic extract of Gomphrena celosioides (EEGc) on reproductive performance, embryo development, and chromosome stability, Swiss mice were randomly divided into experimental groups (n = 10). The animals in the control group received the vehicle Tween 80-1% in the proportion of 0.1 mL/10 g of body weight orally, from the first to the 18th gestational day. The animals in the treatment groups received the EEGc (100, 1000, and 2000 mg/kg) from the first to the 18th gestational day. The animals underwent evaluations of their reproductive performance and embryofetal development. The results showed that the EEGc did not change the animals' final weight, weight gain, uterine weight, or net weight gain. The evaluation showed that the absolute and relative organs' weights did not vary between the different experimental groups. In addition, the EEGc did not change the numbers of implants, live fetuses, dead fetuses, or fetal resorptions. There were no differences in post-operative loss rates, implantations, or resorptions, nor were there differences in fetal viability or sex ratio. The use of the EEGc did not result in different frequencies of malformations. In addition, the EEGc did not alter the frequency of chromosomal damage or frequency of micronuclei. Based on our findings, we considered the extract of Gomphrena celosioides to be safe for use during pregnancy, although some parameters indicated caution in its use.

Curcumin/d-mannitol as photolarvicide: induced delay in larval development time, changes in sex ratio and reduced longevity of Aedes aegypti

BACKGROUND

Resistant populations of Ae. aegypti have been a major problem in arboviruses epidemic areas, generating a strong demand for novel methods of vector control. In this regard, our group has demonstrated the use of curcumin as an efficient photoactive larvicide to eliminate Ae. aegypti larvae. This work was aimed to evaluate the Ae. aegypti (Rockefeller) development under sublethal conditions, using a curcumin/d-mannitol (DMC) formulation. The photolarvicidal efficacy under semi-field and field conditions (wild populations) was also analyzed, as well as the photobleaching and residual activity of DMC.

RESULTS

A delay in development time when larvae were exposed to sublethal concentrations of DMC was observed, followed by significant changes in sex ratio and reduction in longevity. DMC also presented a low residual activity when compared to usual larvicides, and had a substantial photolarvicidal activity against wild populations in field trials, achieving 71.3% mortality after 48 h.

CONCLUSIONS

Overall, these findings are of great biological importance for the process of enabling the implementation of DMC as a new product in the control of Ae. aegypti larvae, and contributes to the improvement of new plant-based larvicides. © 2021 Society of Chemical Industry.

Molecular characterization of the viral structural protein genes in the first outbreak of dengue virus type 2 in Hunan Province, inland China in 2018

Background

An unexpected dengue outbreak occurred in Hunan Province in 2018. This was the first dengue outbreak in this area of inland China, and 172 cases were reported.

Methods

To verify the causative agent of this outbreak and characterise the viral genes, the genes encoding the structural proteins C/prM/E of viruses isolated from local residents were sequenced followed by mutation and phylogenetic analysis. Recombination, selection pressure, potential secondary structure and three-dimensional structure analyses were also performed.

Results

Phylogenetic analysis revealed that all epidemic strains were of the cosmopolitan DENV-2 genotype and were most closely related to the Zhejiang strain (MH010629, 2017) and then the Malaysia strain (KJ806803, 2013). Compared with the sequence of DENV-2SS, 151 base substitutions were found in the sequences of 89 isolates; these substitutions resulted in 20 non-synonymous mutations, of which 17 mutations existed in all samples (two in the capsid protein, six in the prM/M proteins, and nine in the envelope proteins). Moreover, amino acid substitutions at the 602nd (E322:Q → H) and 670th (E390: N → S) amino acids may have enhanced the virulence of the epidemic strains. One new DNA binding site and five new protein binding sites were observed. Two polynucleotide binding sites and seven protein binding sites were lost in the epidemic strains compared with DENV-2SS. Meanwhile, five changes were found in helical regions. Minor changes were observed in helical transmembrane and disordered regions. The 429th amino acid of the E protein switched from a histamine (positively charged) to an asparagine (neutral) in all 89 isolated strains. No recombination events or positive selection pressure sites were observed. To our knowledge, this study is the first to analyse the genetic characteristics of epidemic strains in the first dengue outbreak in Hunan Province in inland China.

Conclusions

The causative agent is likely to come from Zhejiang Province, a neighbouring province where dengue fever broke out in 2017. This study may help clarify the intrinsic geographical relatedness of DENV-2 and contribute to further research on pathogenicity and vaccine development.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05823-3.

Aqueous extract from leaves of Doliocarpus dentatus (Aubl.) Standl. relieves pain without genotoxicity activity

ETHNOPHARMACOLOGICAL RELEVANCE

In the State of Mato Grosso do Sul, the watery sap of Doliocarpus dentatus is used to alleviate thirst, and the leaves of this species are used to relieve pain and swelling associated with inflammatory processes.

AIM OF THE STUDY

This study aimed to analyze the compounds of the leaves from the aqueous extract of D. dentatus (EADd) and evaluate its toxicogenetic and pain relief effects in animal models.

MATERIALS AND METHODS

Compounds were identified in EADd by UHPLC-HRMS (Ultra high-performance liquid chromatography coupled to high resolution mass spectrometry). The oral dose of 17 mg/kg EADd, calculated according to ethnopharmacological uses, and doses between 30 and 300 mg/kg were used to test Swiss mice in formalin- and acetic acid-induced models of pain and behavior. EADd (100-2000 mg/kg) was assayed in mice by comet, micronucleus, and phagocytosis tests and by peripheral leukocyte counts.

RESULTS

Phenolic compounds and flavonoids as well as trigonelline and isoquercetin were identified in EADd. All oral doses of EADd exhibited antinociceptive activity, as indicated by a decrease in pain in both phases, a decrease in cold hypersensitivity induced by formalin, and a decrease in abdominal contortions induced by acetic acid. EADd did not alter the exploratory, motor or motivational activities of the animals. The comet and micronucleus tests indicated that EADd was not genotoxic and did not change the phagocytic activity or peripheral leukocyte count.

CONCLUSIONS

These results demonstrate that EADd could act as an antinociceptive agent that does not present genotoxicity. This study should contribute to justifying, in part, the popular use of D. dentatus in pain management, ensuring its safe use.

Sulphonates' mixtures and emulsions obtained from technical cashew nut shell liquid and cardanol for control of Aedes aegypti (Diptera: Culicidae)

Aedes aegypti is the main mosquito vector of dengue, zika, chikungunya, and yellow fever diseases. The low effectiveness of vector control options is mainly related to the increased insect's resistance and to the toxicity of products used for non-target organisms. The development of new environmentally friendly and safer products is imperative. Technical cashew nut shell liquid (tCNSL), mostly composed by cardanol (C), is an abundant by-product of the cashew (Anacardium occidentale L.) production chain, available at low cost, and with proven larvicidal activity. However, chemical modifications in both tCNSL and cardanol were required to increase their water solubilities. Our objectives were to synthesise and characterise sustainable, low-cost and easy-to-use multiple function products based on tCNSL, cardanol, and the sulphonates obtained from both; and to evaluate all these products efficacy as surfactants, larvicidal, and antimicrobial agents. None of the sulphonates presented antimicrobial and larvicidal activities. tCNSL and cardanol were successfully emulsified with sodium technical cashew nut shell liquid sulphonate (NatCNSLS, complex mixture of surfactants). The emulsions obtained presented larvicidal activity due to the presence of tCNSL and cardanol in their composition. Our results showed that the tCNSL+NatCNSLS mixture emulsion was an effective larvicide and surfactant multiple function product, with high availability and easy-to-use, which can facilitate its large-scale use in different environments. Graphical abstract.

Assessment of acute toxicity and cytotoxicity of fluorescent markers produced by cardanol and glycerol, which are industrial waste, to different biological models

The amphyphylic triazoanilines recently synthesized 1-(4-(3-aminophenyl)-1H-1,2,3- triazole-1-yl)-3-(3-pentadecylphenoxy)propan-2-ol (1) and 1-(4-(4-aminophenyl)-1H- 1,2,3-triazole-1-yl)-3-(3-pentadecylphenoxy)propan-2-ol (2), synthesized from cardanol and glycerol, have photophysical properties which allow their use in the development of fluorescent biomarkers with applicability in the biodiesel quality control. Based on this, the present research evaluated the toxic effects of both compounds in different biological models through the investigation of survival and mortality percentages as a measure of acute toxicity on Daphnia similis and Oreochromis niloticus, larvicidal assay against Aedes aegypti, and cytotoxic activity on mammary cells. Results demonstrate that these triazoanilines 1 and 2 have shown low acute toxicity to the biological models investigated in this study up to the following concentrations: 4.0 mg L-1 (D. similis), 4.0 mg L-1 (A. aegypti larvae), 1.0 mg L-1 (O. niloticus), and 1.0 mg mL-1 (mammary cells). This fact suggests the potential for safe use of compounds 1 and 2 as fluorescent markers for the monitoring of biodiesel quality, even in the case of environmental exposure. Besides all of that, the reuse of cardanol and glycerol, both industrial wastes, favors the maintenance of environmental health and is in agreement with the assumptions of green chemistry. Graphical abstract ᅟ.