Interaction between Haematococcus pluvialis microalgae and lead nitrate: lead adsorption from water.

Our study aims to investigate the response of the unicellular alga, Haematococcus pluvialis, to the toxicity of lead and propose a low-cost, highly efficient biological adsorbent for the purification of wastewater and lead-contaminated water. The first part examines the effects of lead toxicity on certain physiological indicators of this alga. In the second part, the potential of this alga in lead removal and its adsorption capacity was assessed. The alga was cultivated in a BG11 medium and treated with lead nitrate concentrations of 10, 50, and 200 mg/L during its exponential growth. The results showed that with an increase in lead concentration up to 200 mg/L, the growth rate, chlorophyll a, chlorophyll b, carotenoid and total protein content decreased, while malondialdehyde (MDA) content increased. The astaxanthin content slightly increased at the 10 mg/L but decreased at the 200 mg/L treatment. Maximum lead adsorption was observed at 98.69% under optimal conditions, including a pH of 6, an adsorbent dose of 1 g/L, a lead concentration of 25 mg/L, a temperature of 25 °C, and an exposure time of 120 min. The results of this study demonstrate that Haematococcus pluvialis has the potential for effective lead removal from aquatic environments.

While the influence of heavy metals on certain algae species has been explored, research on the impact of lead on Haematococcus pluvialis­a microalga of significant interest for astaxanthin production­remains uncharted territory. Therefore, understanding the impact of this heavy metal and the alga's metal absorption capabilities has profound implications for biotechnology and bioremediation applications. This study promotes H. pluvialis as an economically viable lead absorbent suitable for both industrial and domestic purposes.

Post-harvest ultraviolet irradiation induces changes in physical-chemical properties and levels of polycyclic aromatic hydrocarbons and gene expression in mulberry fruit.

BACKGROUND: Earlier studies reported that post-harvest ultraviolet (UV) irradiation could increase the health-promoting compounds in fruit but the effects of UV irradiation on the reduction of the polycyclic aromatic hydrocarbon (PAH) content in mulberries remain less known. Black mulberry fruit were exposed to two UV illumination dosages (3.5 and 7 kJ m-2 ) and were stored for 4, 8, and 12 days. RESULTS: Mulberries treated in this way displayed higher antioxidant enzyme activity and phenolic compound content in comparison with a control condition. The transcription factors (TFs) MdoMYB121, MdoMYB155, MdbZIP2, and MdbZIP48 were strongly expressed in two UV illumination dosages (about 45-95% higher than the control). The fluorine (Flu) and naphthalene (Nap) content in treated fruit decreased by 21-85% in comparison with the control condition. CONCLUSION: The findings of this study indicate that UV irradiation can be considered as a promising technique to remove some PAHs in black mulberries, to increase their health-promoting potential, and indirectly to improve their aesthetic quality due to the resulting desirable color parameters. © 2023 Society of Chemical Industry.

Targeting Nanog expression increased Cisplatin chemosensitivity and inhibited cell migration in Gastric cancer cells.

Regardless of significant advances in cancer treatment, gastric cancer (GC) incidence rate is increasing worldwide. As one of the main transcription factors participating in stemness, Nanog plays a pivotal role in various aspects of tumorigenesis, metastasis, and chemosensitivity. Given that, the current research intended to evaluate the potential effects of Nanog suppression on the GC cell Cisplatin chemosensitivity and in vitro tumorigenesis. First, bioinformatics analysis was performed to evaluate the effect of Nanog expression on GC patients' survival. The MKN-45 human GC cells were transfected with specific siRNA targeting Nanog and/or treated with Cisplatin. Then, to study cellular viability and apoptosis, MTT assay and Annexin V/PI staining were done, respectively. Also, the scratch assay was performed to investigate cell migration, and MKN-45 cell stemness was followed using colony formation assay. Western blotting and qRT-PCR were used for gene expression analysis. The findings demonstrated that Nanog overexpression was significantly correlated with poor survival of GC patients, and siRNA-mediated Nanog silencing strongly increased MKN-45 cell sensitivity to Cisplatin through apoptosis induction. Also, Nanog suppression combined with Cisplatin resulted in the upregulation of the Caspase-3 and Bax/Bcl-2 ratio at mRNA levels and increased Caspase-3 activation. Moreover, reduced expression of Nanog, separately or combined with Cisplatin, inhibited MKN-45 cell migration by downregulating MMP2 mRNA and protein expression levels. The results also evidenced CD44 and SOX-2 downregulation aligned with a decreased rate of MKN-45 cell colony formation ability through treatments. Besides, Nanog downregulation significantly decreased MDR-1 mRNA expression. Taken together, the results of this study indicated that Nanog could be suggested as a promising target combined with Cisplatin-based GC therapies for reducing drug side effects and improving patients' outcomes.

Silymarin in combination with ATRA enhances apoptosis induction in human acute promyelocytic NB4 cells.

Although all-trans retinoic acid (ATRA) is an efficient pattern in acute promyelocytic leukemia (APL) therapy, further studies are required due to the extant clinical limitations of ATRA. It has been reported that Silymarin, an anti-cancer herbal substance extracted from milk thistle (Silybum marianum), is able to regulate apoptosis in various types of cancer cells through different mechanisms of action. This study investigated the apoptosis-inducing effect of Silymarin (SM) alone and in combination with ATRA on human acute promyelocytic NB4 cells. Examination using MTT assay indicated that SM treatment leads to growth inhibition in NB4 cells in a dose-dependent manner. The IC50 values of SM and ATRA were calculated 90 µM and 2 µM, respectively. Cell cycle analysis by flow cytometry revealed that a more increase in the sub-G1 phase (a sign of apoptosis) when cells were exposed to SM in combination with ATRA. The incidence of apoptosis was confirmed through Hoechst 33258 staining and Annexin V-FITC analysis. The results showed that Silymarin enhances ATRA-induced apoptosis. The flow cytometric analysis also indicated an enhancement in levels of ROS in the treated cells with both compounds. The real-time PCR illustrated that SM targets apoptosis by down-regulation in Survivin and Bcl-2 while up-regulation in Bax. The findings showed that the combination of the two compounds is more effective in the induction of apoptosis in NB4 cells. Molecular docking studies indicated that Sylibin, as a primary compound of the SM, binds to the BH3 domain of Bcl-2 and the BIR domain of Survivin with various affinities. Based on the findings, it seems that SM used alone and in combination with ATRA may be beneficial for inducing apoptosis in APL cells.

Phenanthrene uptake and translocation by Panicum miliaceum L. tissues: an experimental study in an artificial environment.

Polycyclic aromatic hydrocarbons (PAHs), as priority organic pollutants, are capable of accumulation in plants. Phenanthrene (Phe) is one of the most abundant low-molecular-weight PAH in the environment which is commonly used as a model PAH in many phytoremediation studies and as a representative compound for all PAHs group. This paper highlights the uptake, translocation, and accumulation of Phe by growing proso millet (Panicum miliaceum L.) in a pot experiment, subjected to 500, 1000, 1500, and 2000 ppm of Phe treatment after 15 and 30 days. Phe naturally existed in P. miliaceum and its concentration showed a time-dependent reduction in treated plant tissues as well as in perlites. Phe concentration in shoots was higher than in roots. During the aging process, the uptake of Phe was diminished whereas translocation factor (TF) demonstrated an overall increasing trend among treatments. The shoot concentration factor (SCF) values were higher than those of root concentration factor (RCF) on both days 15 and 30 and the highest values for both parameters were achieved in 500 ppm of Phe. Both RCFs and SCFs generally tended to decrease with the increase of perlite Phe concentrations. These results suggested that Phe tended to transfer to the shoots and be metabolized there. The Phe concentration revealed a significant decline in all levels of treatment on both 15 (84 to 96%) and 30 (76 to 94%) days. Therefore, the presence of P. miliaceum was effective in promoting the phytoremediation of Phe polluted perlites.

Nanog suppression enhanced the chemosensitivity of human non-small-cell lung cancer cells to Cisplatin and inhibited cell migration.

Lung cancer is the leading cause of cancer-associated death in the world. As one of the leading transcription factors in controlling stemness features, Nanog was shown to promote cancer progression, metastasis, and drug resistance. Considering that, this research was conducted to evaluate the effect of Nanog suppression using specific siRNA on the chemosensitivity of lung cancer cells to Cisplatin through inhibition of cell proliferation, migration, and stemness as well as apoptosis induction. Then, A549 lung cancer cells were transfected with Nanog siRNA and treated with Cisplatin individually or combined. Subsequently, to investigate cell proliferation and apoptosis induction, MTT assay and Annexin V/PI staining were performed, respectively. Also, colony formation assay was carried out to evaluate cell stemness features, and migration ability of A549 cells was followed using a wound-healing assay. Gene expression was quantified via qRT-PCR. The obtained results illustrated that siRNA-mediated Nanog suppression remarkably increased the chemosensitivity of A549 cells to Cisplatin through apoptosis induction. Consistently, Nanog suppression combined with Cisplatin led to upregulation of Caspase-3 apoptotic gene and Bax/Bcl-2 ratio. Besides, Nanog knockdown, individually or combined with Cisplatin, prevented colony formation ability of A549 cells by downregulating Sox2 and CD44 genes. It was also indicated that the combination therapy remarkably downregulated MMP9 expression and subsequently suppressed A549 cell migration. A significant reduction was also observed in c-Myc and PD-L1 gene expression levels. In conclusion, the findings of the current study demonstrated that silencing Nanog combined with Cisplatin could be a potent treatment approach for lung cancer patients.

Nanog, as a key cancer stem cell marker in tumor progression.

Cancer stem cells (CSCs) are a small population of malignant cells that induce tumor onset and development. CSCs share similar features with normal stem cells in the case of self-renewal and differentiation. They also contribute to chemoresistance and metastasis of cancer cells, leading to therapeutic failure. To identify CSCs, multiple cell surface markers have been characterized, including Nanog, which is found at high levels in different cancers. Recent studies have revealed that Nanog upregulation has a substantial association with the advanced stages and poor prognosis of malignancies, playing a pivotal role through tumorigenesis of multiple human cancers, including leukemia, liver, colorectal, prostate, ovarian, lung, head and neck, brain, pancreatic, gastric and breast cancers. Nanog through different signaling pathways, like JAK/STAT and Wnt/ß-catenin pathways, induces stemness, self-renewal, metastasis, invasiveness, and chemoresistance of cancer cells. Some of these signaling pathways are common in various types of cancers, but some have been found in one or two cancers. Therefore, this review aimed to focus on the function of Nanog in multiple cancers based on recent studies surveying the suitable approaches to target Nanog and inhibit CSCs residing in tumors to gain favorable results from cancer treatments.

siRNA-mediated silencing of Nanog reduces stemness properties and increases the sensitivity of HepG2 cells to cisplatin.

Liver cancer is one of the most lethal cancers having worldwide prevalence. Despite significant progress in cancer therapy, liver cancer-induced mortality is very high. Nanog, as an essential transcription factor modulating cellular multipotency, causes tumor progression, drug resistance, and preserves stemness properties in various tumors such as liver cancer. Thus, this research was conducted to evaluate the impact of combination therapy of Nanog siRNA/cisplatin on the sensitivity of liver cancer cells to this drug. HepG2 cells were transfected with Nanog siRNA and treated with cisplatin, individually and in combination. Then, it was observed that in transfected HepG2 cells, Nanog expression was significantly reduced at mRNA level and also these cells were sensitized to cisplatin. In addition, to assess the impact of Nanog siRNA and cisplatin individually and in combination on cells' viability, migration capacity, apoptosis, and cell cycle progression, the MTT, wound healing, colony formation assay, Annexin V/PI staining, and flow cytometry assays were applied on HepG2 cells, respectively. Also, the quantitive Real-Time PCR was used to check the expression of stemness-associated genes (CD44, CD133, and Sox2), and apoptosis-related genes (caspase-3, 8, 9, BAX and Bcl2) after combination therapy. It is indicated that the combination of Nanog siRNA and cisplatin significantly reduced proliferation, migration, and colony formation ability, as well as increased apoptosis rate, and cell cycle arrest. Also, it is found that the combination of Nanog siRNA and cisplatin down-regulated the expression of stemness-associated genes and up-regulated apoptosis-related genes in HepG2 cells. Hence, it can be suggested that Nanog inhibition in combination with cisplatin is a potential therapeutic strategy for developing new therapeutic approaches for liver cancer.

In vitro study of redroot pigweed effects as weed plant species on leukemia.

Redroot pigweed is a well-known allelopathic weed worldwide with diverse organic compounds which involving in its allelopathic interactions as well. Preliminary tests of redroot pigweed extract against leukemia and various human phatogenic microorganisms revealed that amaranth extract inhibits the viability and proliferation of NB4 cells in a time- and dose-dependent manner and has an excellent anti-bacterial effect on gram-positive bacteria and Candida fungi. Interestingly, the anti-luekemia effects of redroot pigweed is reported for the first time. Phytochemical analysis of redroot pigweed extract, led to the identification amaranth bioactive compounds that largely were including terpenoid compounds (51.71%) as the main group and Carvacrol (11.33%) was the key compound. Redroot pigweed contains various organic compounds with allelopathic and therapeutic properties and current investigation is a promising revelation for the pharmaceutical importance of this plant.

Are biosynthesized nanomaterials toxic for the environment? Effects of perlite and CuO/perlite nanoparticles on unicellular algae Haematococcus pluvialis.

The properties of nanomaterials such as perlite nanoparticles and their increased application have raised concerns about their probable toxic impacts on the aquatic ecosystems and algae. Here, a novel biochemical synthesis and immobilization of CuO is reported on perlite nanoparticles (CuO/Per-NPs) and its toxic effect on alga has been compared with nanoperlites. This biosynthesis of CuO/Per-NPs performed using phytochemicals of Haematococcus pluvialis, Sargassum angustifolium, and walnut leaves in the aqueous extract. The structural, morphological, and colloidal properties of the as-synthesized nanoparticles have been confirmed by various methods. According to the obtained results, the morphology of the synthesized CuO/Per-NPs was spherical with sizes ranging from about 13 to 24 nm. Besides, the effects of Per-NPs and CuO/Per-NPs on unicellular algae H. pluvialis were studied. The changes in the amount of chlorophyll a, chlorophyll b, and Carotenoids in the presence of different concentrations of Per-NPs (25, 50, 100 mg/L) were more than CuO/Per-NPs. Also, decreased growth rate and efficiency of photosystem II confirmed the toxic effects of Per-NPs. However, the toxicity of CuO/Per-NPs appears to be lower than that of Per-NPs, which can be due to the changes in the surface and cationic charge of modified nanoperlit. These changes lead to a decrease in the interaction of nanoparticles with H. pluvilalis and a reduction in ROS production. Finally, the results of GC-MS used to evaluate volatile compounds, indicated an increase in the number of phenolic compounds in comparison to the control samples in 25, 50, and 100 mg/L treatments of nano-perlite.

Changes in antioxidants and leaf pigments of safflower (Carthamus tinctorius L.) affected by exogenous spermine under water deficit.

Water deficit is one of the most limiting factors for plant growth and production. Polyamines are osmo-active compounds and have important roles in plant resistance to water limitation. A pot experiment was undertaken in a greenhouse as factorial based on complete randomized block design with three replications to assess the physiological and biochemical responses of safflower to different levels of water supply (100% and 40% field capacity) and spermine (0, 40 and 60 µM). Ascorbate peroxidase and peroxidase activities (POX), malondialdehyde (MDA), hydrogen peroxide (H2O2), anthocyanins, soluble protein, soluble sugars and proline contents in shoots increased, while total phenols, flavonoids, and photosynthetic pigments significantly decreased due to water deficit. Foliar spray of spermine mitigated the adverse effects of water deficit by increasing the catalase, superoxide dismutase, POX activities, soluble proteins and photosynthetic pigments, and by decreasing MDA and H2O2 contents. Spermine could, therefore, play an important role in protecting photosynthetic system and cellular membranes during drought stress in safflower.

Free radical scavenging and antioxidant activity of betanin: electron spin resonance spectroscopy studies and studies in cultured cells.

Betanin is a red pigment present in red beetroot. Recently, potential health benefits of betanin-rich beetroot have been suggested. However, little is known regarding the free radical scavenging and antioxidant activity of betanin. Electron spin resonance spectroscopy (ESR) and spin trapping techniques were applied to evaluate the ability of betanin to scavenge hydroxyl, superoxide, 2,2 diphenyl-1-picrylhydrazyl (DPPH), and galvinoxyl free radicals. In addition, we tested in cultured cells the ability of betanin to prevent DNA damage and to induce the transcription factor Nrf2 (nuclear factor (erythroid-derived 2)-like 2) as well as its down-stream target heme oxygenase1 (HO-1), paraoxonase1 (PON1) and glutathione (GSH). Betanin dose-dependently scavenged DPPH-, galvinoxyl-, superoxide-, and hydroxyl-radicals in the ESR and spin trapping studies and prevented hydrogen peroxide induced DNA damage as determined by the Comet assay. Furthermore, betanin treatment induced the transcription factor Nrf2 and resulted in an increase of HO-1 protein levels, PON1-transactivation and cellular GSH. Present data suggest that betanin is both a free radical scavenger and an inducer of antioxidant defense mechanism in cultured cells.

Simple HPLC evaluation of lipoamidase activity in tissue using a newly synthesized fluorescent substrate, dansyl-α-lipoyllysine.

α-Lipoic acid (LA) is a naturally occurring disulfide-containing compound used as an antioxidant supplement which also has been used as a medicine for diabetic neuropathy in Europe. Physiologically LA acts as a coenzyme of mitochondrial multienzyme complex in its protein bound form but it is not yet clear how the externally administrated LA is incorporated into other proteins in the same protein-bound form or why the bound form is active as an antioxidant. The binding and cleavage of LA to or from the protein is mediated by lipoamidase and thus determines LA distribution in tissues. We have developed a simple sensitive assay for lipoamidase using a fluorescent substrate, dansyl-α-lipoyllysine (DLL). Lipoamidase in tissues cleaves the amide bond between LA and the ε-amino-lysine moiety to release dansylated lysine (DL). A HPLC comparison of the fluorescence intensity between DLL and DL was used to quantify the enzyme activity. The hydrolytic reaction did not occur when the tissue was heat-treated before incubation with DLL and was inhibited by free LA, especially by the R-enantiomer of LA (physiologically active form). N(ε)-Acetyl-L-lysine did not compete with DLL in the cleavage reaction. The method was applied for the determination of lipoamidase activity levels in various rat tissues. It was revealed the spleen had the highest activity followed by the kidney, heart, lung and liver. The activity in the brain was below the detection limit of the assay.