Bacopa monnieri Phytochemicals Mediated Synthesis of Platinum Nanoparticles and Its Neurorescue Effect on 1-Methyl 4-Phenyl 1,2,3,6 Tetrahydropyridine-Induced Experimental Parkinsonism in Zebrafish

Abstract

Current discovery demonstrates the rapid formation of platinum nanoparticles using leaf extract of a neurobeneficial plant, Bacopa monnieri (BmE). The nanoparticles (BmE-PtNPs) were stabilized and then coated with varied phytochemicals present within the leaf extract. These nanoparticles demonstrated the same activity of Complex I, as that of oxidizing NADH to NAD(+) using a spectrophotometric method. This suggests that BmE-PtNPs are a potential medicinal substance for oxidative stress mediated disease with suppressed mitochondrial complex I, namely, Parkinson's disease (PD). Hence, the neuroprotective potentials of the phytochemical coated nanoparticle were explored in 1-methyl 4-phenyl 1,2,3,6 tetrahydropyridine- (MPTP-)induced experimental Parkinsonism in zebrafish model. BmE-PtNPs pretreatment significantly reversed toxic effects of MPTP by increasing the levels of dopamine, its metabolites, GSH and activities of GPx, catalase, SOD and complex I, and reducing levels of MDA along with enhanced locomotor activity. Taken together, these findings suggest that BmE-PtNPs have protective effect in MPTP-induced neurotoxicity in this model of Parkinson's disease via their dual functions as mitochondrial complex I and antioxidant activity.

Figure 1

Characterization of Bacopa monnieri phytochemicals coated platinum nanoparticles (BmE-PtNPs). (a) UV-Vis Spectra of BmE-PtNPs. The inset shows two bottles with the Bacopa monnieri leaf extract before (A) and after (B) reaction with 1 mM PtCl₆ ²⁻ ions for 3 hrs at 95°C. A color version of the inset can be seen. (b) TEM images of BmE-PtNPs. (c) EDAX of BmE-PtNPs. (d) FTIR spectra of BmE-PtNPs.

Figure 2

Change in absorption spectra at 3 h and 6 h, respectively. BmEPt nps were incubated with NADH in water at room temperature. The concentrations of platinum in BmE-PtNPs and NADH were 50 μg/mL and 100 μM, respectively.

Figure 3

(a) Effects of Bacopa monnieri phytochemicals coated platinum nanoparticles (BmE-PtNPs) on the content/activity of MDA, GSH, SOD, GSH-Px, and CAT in the MPTP zebrafish brain. Data were shown as mean ± SEM. n = 6–8, ^∗#†$‡ P < 0.05, ^{∗∗##††$$‡‡} P < 0.01, ^{∗∗∗###†††$$$‡‡‡} P < 0.001 versus MPTP group. (b) Effects of Bacopa monnieri phytochemicals coated platinum nanoparticles (BmE-PtNPs) on the activity of complex I in the MPTP zebrafish brain. Data were shown as mean ± SEM. n = 6–8, ^* P < 0.05, ^** P < 0.01, ^*** P < 0.001 versus MPTP group.

Figure 4

Effects of Bacopa monnieri phytochemicals coated platinum nanoparticles (BmE-PtNPs) on the contents of dopamine, DOPAC, and HVA in the MPTP zebrafish brain. Data were shown as mean + SEM. n = 6–8, ^∗†‡ P < 0.05, ^{∗∗††‡‡} P < 0.01, ^{∗∗∗†††‡‡‡} P < 0.001 versus MPTP group.

Figure 5

Effects of Bacopa monnieri phytochemicals coated platinum nanoparticles (BmE-PtNPs) on zebrafish brain locomotor activity. Data were shown as mean ± SEM. n = 6–8; one-way ANOVA test was performed.