* Indexes up: Dow 0.63%, S&P 500 0.17%, Nasdaq 0.14%

* Apple ( AAPL ) names hardware veteran Ternus as new CEO to

succeed Cook

* Amazon ( AMZN ) climbs after pledging to invest up to $25 bln in

Anthropic

* UnitedHealth ( UNH ) gains after raising FY profit outlook

(Updates after markets open)

By Niket Nishant and Avinash P

April 21 (Reuters) - Wall Street's main indexes inched

higher on Tuesday as renewed artificial intelligence optimism

and strong corporate earnings bolstered markets battered by

constant back-and-forth over the resolution of the Middle East

conflict.

J.P. Morgan raised its year-end target for the S&P 500,

citing AI and tech-driven earnings, while Amazon ( AMZN ) said

on Monday it will invest up to $25 billion in Anthropic,

signaling Big Tech is still willing to pour money into AI.

Amazon ( AMZN ) shares rose 2%, helping the S&P 500 consumer

discretionary sector jump nearly 1% to become the

biggest gainer on the benchmark. A 0.5% decline in the

healthcare sector limited gains in the S&P 500.

Investors are also awaiting the Senate confirmation hearing

for Kevin Warsh, U.S. President Donald Trump's nominee to lead

the Federal Reserve.

Republican Senator Thom Tillis has promised to block the

confirmation until the Department of Justice ends an

investigation into Fed Chair Jerome Powell that Tillis says

threatens the central bank's independence.

The hearing could have far-reaching implications for

monetary policy, especially as Trump has vowed to fire Powell if

he does not leave when his term ends in May.

At 09:45 a.m. ET, the Dow Jones Industrial Average

rose 309.83 points, or 0.63%, to 49,752.39, the S&P 500

gained 12.30 points, or 0.17%, to 7,121.44 and the Nasdaq

Composite gained 34.10 points, or 0.14%, to 24,438.49.

Despite the uncertainty, AI hopes and upbeat earnings

prevented investors from retreating to the sidelines.

Of the 48 companies in the benchmark S&P 500 index

that reported earnings as of last Friday, 87.5% surpassed

analysts' estimates, compared with a long-term average of 67.4%,

according to LSEG data.

The earnings have been strong and are overpowering the

narrative, said Thomas Hayes, chairman at Great Hill Capital.

UnitedHealth ( UNH ) jumped 9.2% after the healthcare

conglomerate raised its annual profit forecast and beat Wall

Street expectations for the first quarter. The stock was the

biggest boost to the blue-chip Dow.

Peers CVS Health ( CVS ) and Humana rose 1.7% and

5.2%, respectively.

GE Aerospace fell 3.1%. The company said it was

bracing for a tougher backdrop of elevated oil prices, fuel

supply constraints and slower global growth.

WAR FUELS VOLATILITY

Markets have been pulled in opposite directions by a torrent

of conflicting headlines in recent days.

On Friday, Tehran's vow to reopen the Strait of Hormuz -- a

crucial waterway for oil shipping -- briefly sparked hopes for

de-escalation, which quickly faded over the weekend when Iran

fired what appeared to be warning shots at vessels and the U.S.

military seized an Iranian cargo ship.

In an interview with CNBC on Tuesday, Trump said the U.S.

would end up with a "great deal" with Iran. However, uncertainty

around the end of the two-week ceasefire loomed.

Alaska Air ( ALK ) fell 1.3% as the airline withdrew its

full-year profit forecast.

Apple ( AAPL ) was among the other stocks under the

spotlight, falling 0.5% after the company said CEO Tim Cook

would hand over the reins to longtime hardware boss John Ternus.

Separately, data showed that U.S. retail sales increased

more than expected in March.

Advancing issues outnumbered decliners by a 1.44-to-1 ratio

on the NYSE and by a 1.07-to-1 ratio on the Nasdaq.

The S&P 500 posted 41 new 52-week highs and 2 new lows,

while the Nasdaq Composite recorded 100 new highs and 23 new

lows.

(Reporting by Niket Nishant and Avinash P in Bengaluru; Editing

by Devika Syamnath and Shinjini Ganguli)